View source for Paper size

{{Short description|Standard sizes of paper}}
{{For|sizing as the ingredient used in papermaking|Sizing#Papermaking}}
{{Use British English |date=January 2024}}
{{Use dmy dates|date=September 2021|cs1-dates=y}}
[[File:PapierformateA0bisA8.jpg|thumb|Paper sizes A0 to A8, life-size installation ''The Invasion of the Square Roots'' at the [[CosmoCaixa Barcelona]] science museum]]
[[File:A size illustration2 with letter and legal.svg|thumb|right|A size chart illustrating the ISO A series and a comparison with American letter and legal formats]]
[[File:Comparison paper sizes.svg|thumb|Comparison of some paper and photographic paper sizes close to the A4 size]]

'''Paper size''' [[Technical standard|standards]] govern the size of sheets of paper used as writing paper, stationery, cards, and for some printed documents.

The [[ISO 216]] standard, which includes the commonly used A4 size, is the [[international standard]] for paper size. It is used across the world except in North America and parts of Central and South America, where [[#North American paper sizes|North American paper sizes]] such as "[[Letter (paper size)|Letter]]" and "[[Legal paper|Legal]]" are used.<ref name="CLDR"/> The international standard for envelopes is the [[#ISO C|C series]] of [[ISO 269]].

== International standard paper sizes <span class="anchor" id="International paper sizes"></span>==
[[File:Prevalent default paper size.svg|thumb|Map of the world showing adoption of paper sizes, according to the [[Common Locale Data Repository]] in 2017
{{legend|#0000BB|ISO A4 exclusively}}
{{legend|#4444BB|ISO A4 primarily}}
{{legend|#FF8888|US-Letter primarily}}
{{legend|#FF0000|US-Letter predominantly}}
{{legend|#BB0000|US-Letter exclusively}}
]]

{{Main|ISO 216}}
{{Hatnote|See [[Switching barriers|Switching costs]], [[Network effect]]s and [[Standardization]] for possible reasons for differing regional adoption rates of the [[International Organization for Standardization|ISO]] standard sizes.}}

The international paper size standard is [[ISO 216]].  It is based on the German [[Deutsches Institut für Normung|DIN]] 476 standard for paper sizes. Each ISO paper size is one half of the area of the next larger size in the same series. ISO paper sizes are all based on a single [[aspect ratio (image)|aspect ratio]] of the [[square root of 2]], or approximately 1:1.41421. There are different series, as well as several extensions.

The following international paper sizes are included in [[Cascading Style Sheets]] (CSS): ''A3'', ''A4'', ''A5'', ''B4'', ''B5''.<ref name="mozilla.org">{{cite web |url=https://developer.mozilla.org/en-US/docs/Web/CSS/@page/size|title=size |access-date=25 January 2017 |archive-url=https://web.archive.org/web/20170202023142/https://developer.mozilla.org/en-US/docs/Web/CSS/@page/size|archive-date=2 February 2017 |url-status=live}}</ref>

{{anchor|ISO A|DIN A|SIS A|JIS A}}
=== A series ===
[[File:A size illustration2.svg|thumb|right|A size chart illustrating the ISO A series]]

There are 11 sizes in the A series, designated A0–A10, all of which have an aspect ratio of <math>\frac{a}{b} = \sqrt{2} \approx 1.41421\ldots</math>, where ''a'' is the long side and ''b'' is the short side.

Since A series sizes share the same aspect ratio <math>(\sqrt{2}),</math> they can be scaled to other A series sizes without being distorted, and two sheets can be reduced to fit on exactly one sheet without any cutoff or margins.

The A0 base size is defined as having an area of 1&nbsp;m{{sup|2}}; given an aspect ratio of <math>\sqrt{2}</math>, the dimensions of A0 are:

: <math>\sqrt[4]2\,\mathrm{m}</math> by <math>\frac1\sqrt[4]2\,\mathrm{m}</math>.

or, rounded to the nearest millimetre, {{convert|1189|x|841|mm|inch|abbr=on}}.

A series sizes are related in that the smaller dimension of a given size is the larger dimension of the next smaller size, and folding an A series sheet in half in its larger dimension—that is, folding it in half parallel to its short edge—results in two halves that are each the size of the next smaller A series size. As such, a folded brochure of a given A-series size can be made by folding sheets of the next larger size in half, e.g. A4 sheets can be folded to make an A5 brochure. The fact that halving a sheet with an aspect ratio of <math>\sqrt{2}</math> results in two sheets that themselves both have an aspect ratio of <math>\sqrt{2}</math> is proven as follows:

: <math>\frac{a}{b} = \sqrt{2},</math>

where ''a'' is the long side and ''b'' is the short side. The aspect ratio for the new dimensions of the folded paper is:

: <math>\frac{b}{\frac{a}{2}} = 2\frac{b}{a} = 2\frac{1}{\sqrt{2}} = \sqrt{2} = \frac{a}{b}.</math>

The advantages of basing a paper size upon an aspect ratio of <math>\sqrt{2}</math> were noted in 1786 by the German scientist and philosopher [[Georg Christoph Lichtenberg]].<ref>{{cite web |url=http://www.cl.cam.ac.uk/~mgk25/lichtenberg-letter.html |title=Lichtenberg's letter to Johann Beckmann |publisher=Markus Kuhn |date=7 February 2006 |access-date=3 April 2023 |archive-url=https://web.archive.org/web/20111231214454/http://www.cl.cam.ac.uk/~mgk25/lichtenberg-letter.html |archive-date=31 December 2011 |url-status=live}}</ref> He also observed that some raw sizes already adhered to that ratio so that when a sheet is folded, the length to width ratio does not change.

Briefly after the introduction of the [[metric system]], a handful of new paper formats equivalent to modern ones were developed in France, having been proposed by the mathematician [[Lazare Carnot]], and published for judicial purposes in 1798 during the [[French Revolution]].<ref name="B237">{{cite journal |title=Loi sur le timbre (Nº 2136) |trans-title=Stamp Act (No. 2136) |date=3 November 1798 |journal=Bulletin des Lois de la République |issue=237 |pages=1–2 |language=fr |publisher=Republic of France |location=Paris |url=http://www.cl.cam.ac.uk/~mgk25/loi-timbre.html |url-status=live |access-date=2024-01-20 |archive-url=https://web.archive.org/web/20090426170239/http://www.cl.cam.ac.uk/~mgk25/loi-timbre.html |archive-date=26 April 2009 |via=Markus Kuhn }}</ref> These were never widely adopted, however:

* ''grand registre'' (A2)
* ''moyen papier'' (A3)
* ''grand papier'' (B3)
* ''petit papier'' (B4)
* ''demi feuille'' (B5)
* ''effets de commerce'' (half-B5)

Early in the 20th century, the ratio was used to specify the [[#Weltformat|''world format'']] starting with 1&nbsp;cm as the short edge of the smallest size. Walter Porstmann started with the largest sizes instead, assigning one an area of 1&nbsp;m<sup>2</sup> (A0) and the other a short edge of 1&nbsp;m (B0). He thereby turned the forgotten French sizes (relatively few in number) into a logically-simple and comprehensive plan for a full range of paper sizes, while introducing systematic alphanumeric monikers for them. Generalized to nothing less than four series, this system was introduced as a [[#German original|DIN standard (DIN 476)]] in Germany in 1922, replacing a vast variety of other paper formats. Even today, the paper sizes are called "DIN A4" ({{IPA|de|diːn.ʔaː.fiːɐ̯|IPA}}) in everyday use in Germany and Austria.

The DIN 476 standard spread quickly to other countries. Before the outbreak of [[World War II]], it had been adopted by the following countries in Europe:

{{div col|colwidth=22em}}
* [[Belgium]] (1924)
* [[Netherlands]] (1925)
* [[Norway]] (1926)
* [[Finland]] (1927)
* [[Switzerland]] (1929)
* Sweden (1930) with [[#Swedish extension|later extensions]]
* [[Soviet Union]] (1934) with [[#Soviet variants|custom extensions]]
* [[Hungary]] (1938)
* Italy (1939)
{{div col end}}

During World War II, the standard spread to South America and was adopted by [[Uruguay]] (1942), [[Argentina]] (1943) and Brazil (1943), and afterwards spread to other countries:

{{div col|colwidth=22em}}
* [[Australia]] (1974)
* [[Austria]] (1948)
* [[Bangladesh]] (1972)
* [[Barbados]] (1973)
* [[Chile]] (1968)
* [[Colombia]] (1975)
* [[Czechoslovakia]] (1953)
* [[Denmark]] (1953)
* [[Ecuador]] (1974)
* [[France]] (1967)
* [[Greece]] (1970)
* [[Iceland]] (1964)
* [[India]] (1957) with [[#Indian variants|custom extensions]]
* [[Iran]] (1948)
* [[Ireland]] (1959)
* [[Israel]] (1954)
* [[Japan]] (1951) with [[#Japanese variation|different B series]]
* [[Kuwait]] (1975)
* [[Mexico]] (1965)
* [[New Zealand]] (1963)
* [[Peru]] (1967)
* [[Poland]] (1957)
* [[Portugal]] (1954)
* [[Rhodesia]] (1970)
* [[Romania]] (1949)
* [[Singapore]] (1970)
* [[South Africa]] (1966)
* [[Spain]] (1947)
* [[Thailand]] (1973)
* [[Turkey]] (1967)
* [[United Kingdom]] (1971)<ref>{{cite web|author=Metrication Board|title=Final report of the Metrication Board|date=1980|publisher=Department of Trade and Industry Consumer and Competition Policy Directorate|page=17|url=http://ukma.org.uk/sites/default/files/met1980.pdf|archive-url=https://web.archive.org/web/20130501034405/http://ukma.org.uk/sites/default/files/met1980.pdf|access-date=29 September 2021|archive-date=1 May 2013}}</ref>
* [[Venezuela]] (1962)
* [[SFRY|Yugoslavia]](1956)
{{div col end}}

By 1975, so many countries were using the German system that it was established as an [[International Organization for Standardization|ISO]] standard, as well as the official United Nations document format. By 1977, A4 was the standard letter format in 88 of 148 countries. Today the standard has been adopted by all countries in the world except the United States and Canada. In Mexico, [[Costa Rica]], [[Colombia]], [[Venezuela]], Chile, and the [[Philippines]], the [[Letter (paper size)|US letter]] format is still in common use, despite their official adoption of the ISO standard.

The weight of an A-series sheet of a given [[Paper density#Basis weight|paper weight]] can be calculated by knowing the ratio of its size to the A0 sheet. For example, an A4 sheet is {{frac|16}} the size of an A0 sheet, so if it is made from {{nowrap|80-g/m{{sup|2}}}} paper, it weighs {{frac|16}} of 80&nbsp;g, which is 5&nbsp;g.

{{anchor|ISO B|DIN B|SIS B}}

=== B series ===
[[File:B size illustration2.svg|thumb|right|A size chart illustrating the ISO B series]]

The B series paper sizes are less common than the A series. They have the same aspect ratio as the A series:

::<math>\frac{a}{b}=\sqrt{2} = 1.41421...</math>

However, they have a different area. The area of B series sheets is in fact the [[geometric mean]] of successive A series sheets. B1 is between A0 and A1 in size, with an area of <math>\frac{1}{\sqrt{2}}</math> m{{sup|2}}, or about 0.707&nbsp;m{{sup|2}}. As a result, B0 is 1 metre wide, and other sizes of the series are a half, a quarter, or further fractions of a metre wide: in general, every B size has exactly one side of length <math>\frac{1 \operatorname{m}}{2^n}</math> for <math>n \in \mathbb{N}</math>. That side is the short side for B0, B2, B4, etc., and the long side for B1, B3, B5, etc.

While less common in office use, the B series is used for a variety of applications in which one A-series size would be too small but the next A-series size is too large, or because they are convenient for a particular purpose.

* B4, B5, and B6 are used for [[envelope]]s that will hold C-series envelopes.
* B4 is quite common in printed music sheets.
* B5 is a relatively common choice for books.
* B7 is equal to the passport size ID-3 from [[ISO/IEC 7810]].
* Many posters use B-series paper or a close approximation, such as 50&nbsp;cm × 70&nbsp;cm ~ B2.

<!--someone please confirm the validity of the following sentences:-->
The B-series is widely used in the printing industry to describe both paper sizes and [[printing press]] sizes, including [[digital printing|digital presses]]. B3 paper is used to print two US letter or A4 pages side by side using [[imposition]]; four pages would be printed on B2, eight on B1, etc.{{qn|date=January 2020}}

{{anchor|ISO C|DIN C|SIS C}}

=== C series ===
[[File:C size illustration2.svg|thumb|right|A size chart illustrating the ISO C series]]
The C series is defined in [[ISO 269]], which was withdrawn in 2009 without a replacement, but is still specified in several national standards. It is primarily used for envelopes. The area of C series sheets is the geometric mean of the areas of the [[#ISO A|A]] and [[#ISO B|B series]] sheets of the same number; for instance, the area of a C4 sheet is the geometric mean of the areas of an A4 sheet and a B4 sheet. This means that C4 is slightly larger than A4, and slightly smaller than B4. The practical usage of this is that a letter written on A4 paper fits inside a C4 envelope, and both A4 paper and C4 envelope fits inside a B4 envelope.

Some envelope formats with mixed sides from adjacent sizes (and thus an approximate aspect ratio of 2:1) are also defined in national adaptations of the ISO standard, e.g. DIN C6/C5 (also known as C65) is 114&nbsp;mm × 229&nbsp;mm where the common side to C5 and C6 is 162&nbsp;mm. This format allows an envelope holding an A-sized paper folded in three, e.g. for the C65, an A4.

=== Overview of ISO paper sizes ===
{| class="wikitable" style="text-align: center;"
|+ ISO paper sizes in portrait view (with rounded inch values)
! Format
!colspan="3"| [[#ISO A|A series]]<ref>{{cite web |url=http://www.papersizes.org/a-paper-sizes.htm |title=A Paper Sizes - A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10 |access-date=25 January 2017 |archive-url=https://web.archive.org/web/20161029141208/http://www.papersizes.org/a-paper-sizes.htm |archive-date=29 October 2016 |url-status=live}}</ref>
!colspan="3"| [[#ISO B|B series]]<ref>{{cite web |url=http://www.papersizes.org/b-paper-sizes.htm |title=B Paper Sizes - B0, B1, B2, B3, B4, B5, B6, B7, B8, B9, B10 |access-date=25 January 2017 |archive-url=https://web.archive.org/web/20161204151334/http://www.papersizes.org/b-paper-sizes.htm |archive-date=4 December 2016 |url-status=live}}</ref>
!colspan="3"| [[#ISO C|C series]]<ref>{{cite web |url=http://www.papersizes.org/c-envelope-sizes.htm |title=Envelope Sizes - ISO C Series & DL Envelopes |access-date=25 January 2017 |archive-url=https://web.archive.org/web/20161204141443/http://www.papersizes.org/c-envelope-sizes.htm |archive-date=4 December 2016 |url-status=live}}</ref>
|-
! rowspan="2" | Size
!colspan="2" | short × long || Notional area
!colspan="2" | short × long || Notional area
!colspan="2" | short × long || Notional area
|-
! mm || in || m<sup>2</sup>
! mm || in || m<sup>2</sup>
! mm || in || m<sup>2</sup>
|-
! 0
|  841 × 1189 || {{nowrap|{{convert |  841 x 1189 | mm | 1 | abbr=values | disp=out}}}} {{anchor|A0}} || 2<sup>0</sup> = 1
| 1000 × 1414 || {{nowrap|{{convert | 1000 x 1414 | mm | 1 | abbr=values | disp=out}}}} {{anchor|B0}} || 2<sup>{{frac|1|2}}</sup> ≈ {{round|1.4142135624|3}}
|  917 × 1297 || {{nowrap|{{convert |  917 x 1297 | mm | 1 | abbr=values | disp=out}}}} {{anchor|C0}} || 2<sup>{{frac|1|4}}</sup> ≈ {{round|1.189207115|3}}
|-
! 1 
|   594 × 841 || {{nowrap|{{convert |  594 x  841 | mm | 1 | abbr=values | disp=out}}}} {{anchor|A1}} || 1/2 = 0.5
|  707 × 1000 || {{nowrap|{{convert |  707 x 1000 | mm | 1 | abbr=values | disp=out}}}} {{anchor|B1}} || 2<sup>−{{frac|1|2}}</sup> ≈ {{round|0.7071067812|3}}
|   648 × 917 || {{nowrap|{{convert |  648 x  917 | mm | 1 | abbr=values | disp=out}}}} {{anchor|C1}} || 2<sup>−{{frac|3|4}}</sup> ≈ {{round|0.5946035575|3}}
|-
! 2 
|   420 × 594&nbsp;|| {{nowrap|{{convert |  420 x  594 | mm | 1 | abbr=values | disp=out}}}} {{anchor|A2}} || 1/2<sup>2</sup> = 0.25
|   500 × 707 || {{nowrap|{{convert |  500 x  707 | mm | 1 | abbr=values | disp=out}}}} {{anchor|B2}} || 2<sup>−{{frac|1|1|2}}</sup> ≈ {{round|0.3535533906|3}}
|   458 × 648 || {{nowrap|{{convert |  458 x  648 | mm | 1 | abbr=values | disp=out}}}} {{anchor|C2}} || 2<sup>−{{frac|1|3|4}}</sup> ≈ {{round|0.2973017788|3}}
|-
! 3
|   297 × 420 || {{nowrap|{{convert |  297 x  420 | mm | 1 | abbr=values | disp=out}}}} {{anchor|A3}} || 1/2<sup>3</sup> = 0.125
|   353 × 500 || {{nowrap|{{convert |  353 x  500 | mm | 1 | abbr=values | disp=out}}}} {{anchor|B3}} || 2<sup>−{{frac|2|1|2}}</sup> ≈  {{round|0.1767766953|3}}
|   324 × 458 || {{nowrap|{{convert |  324 x  458 | mm | 1 | abbr=values | disp=out}}}} {{anchor|C3}} || 2<sup>−{{frac|2|3|4}}</sup> ≈  {{round|0.1486508894|3}}
|-
! 4
|   210 × 297 || {{nowrap|{{convert |  210 x  297 | mm | 1 | abbr=values | disp=out}}}} {{anchor|A4}} || 1/2<sup>4</sup> = 0.0625
|   250 × 353 || {{nowrap|{{convert |  250 x  353 | mm | 1 | abbr=values | disp=out}}}} {{anchor|B4}} || 2<sup>−{{frac|3|1|2}}</sup> ≈  {{round|0.0883883476|3}}
|   229 × 324 || {{nowrap|{{convert |  229 x  324 | mm | 1 | abbr=values | disp=out}}}} {{anchor|C4}} || 2<sup>−{{frac|3|3|4}}</sup> ≈  {{round|0.0743254447|4}}
|-
! 5
|   148 × 210 || {{nowrap|{{convert |  148 x  210 | mm | 1 | abbr=values | disp=out}}}} {{anchor|A5}} || 1/2<sup>5</sup> ≈ {{round|0.03125|4}}
|   176 × 250 || {{nowrap|{{convert |  176 x  250 | mm | 1 | abbr=values | disp=out}}}} {{anchor|B5}} || 2<sup>−{{frac|4|1|2}}</sup> ≈  {{round|0.0441941738|3}}
|   162 × 229 || {{nowrap|{{convert |  162 x  229 | mm | 1 | abbr=values | disp=out}}}} {{anchor|C5}} || 2<sup>−{{frac|4|3|4}}</sup> ≈  {{round|0.0371627223|4}}
|-
! 6
|   105 × 148 || {{nowrap|{{convert |  105 x  148 | mm | 1 | abbr=values | disp=out}}}} {{anchor|A6}} || 1/2<sup>6</sup> ≈ {{round|0.015625|4}}
|   125 × 176 || {{nowrap|{{convert |  125 x  176 | mm | 1 | abbr=values | disp=out}}}} {{anchor|B6}} || 2<sup>−{{frac|5|1|2}}</sup> ≈  {{round|0.0220970869|4}}
|   114 × 162 || {{nowrap|{{convert |  114 x  162 | mm | 1 | abbr=values | disp=out}}}} {{anchor|C6}} || 2<sup>−{{frac|5|3|4}}</sup> ≈  {{round|0.0185813612|4}}
|-
! 7
|    74 × 105 || {{nowrap|{{convert |   74 x  105 | mm | 1 | abbr=values | disp=out}}}} {{anchor|A7}} || 1/2<sup>7</sup> ≈ {{round|0.0078125|4}}
|    88 × 125 || {{nowrap|{{convert |   88 x  125 | mm | 1 | abbr=values | disp=out}}}} {{anchor|B7}} || 2<sup>−{{frac|6|1|2}}</sup> ≈  {{round|0.0110485435|4}}
|    81 × 114 || {{nowrap|{{convert |   81 x  114 | mm | 1 | abbr=values | disp=out}}}} {{anchor|C7}} || 2<sup>−{{frac|6|3|4}}</sup> ≈  {{round|0.0092906806|4}}
|-
! 8
|     52 × 74 || {{nowrap|{{convert |   52 x   74 | mm | 1 | abbr=values | disp=out}}}} {{anchor|A8}} || 1/2<sup>8</sup> ≈ {{round|0.00390625|4}}
|     62 × 88 || {{nowrap|{{convert |   62 x   88 | mm | 1 | abbr=values | disp=out}}}} {{anchor|B8}} || 2<sup>−{{frac|7|1|2}}</sup> ≈  {{round|0.0055242717|4}}
|     57 × 81 || {{nowrap|{{convert |   57 x   81 | mm | 1 | abbr=values | disp=out}}}} {{anchor|C8}} || 2<sup>−{{frac|7|3|4}}</sup> ≈  {{round|0.0046453403|4}}
|-
! 9
|     37 × 52 || {{nowrap|{{convert |   37 x   52 | mm | 1 | abbr=values | disp=out}}}} {{anchor|A9}} || 1/2<sup>9</sup> ≈ {{round|0.001953125|4}}
|     44 × 62 || {{nowrap|{{convert |   44 x   62 | mm | 1 | abbr=values | disp=out}}}} {{anchor|B9}} || 2<sup>−{{frac|8|1|2}}</sup> ≈  {{round|0.0027621359|4}}
|     40 × 57 || {{nowrap|{{convert |   40 x   57 | mm | 1 | abbr=values | disp=out}}}} {{anchor|C9}} || 2<sup>−{{frac|8|3|4}}</sup> ≈  {{round|0.0023226701|4}}
|-
! 10
|     26 × 37 || {{nowrap|{{convert |   26 x   37 | mm | 1 | abbr=values | disp=out}}}} {{anchor|A10}} || 1/2<sup>10</sup> ≈ {{round|0.0009765625|5}}
|     31 × 44 || {{nowrap|{{convert |   31 x   44 | mm | 1 | abbr=values | disp=out}}}} {{anchor|B10}} || 2<sup>−{{frac|9|1|2}}</sup> ≈  {{round|0.0013810679|4}}
|     28 × 40 || {{nowrap|{{convert |   28 x   40 | mm | 1 | abbr=values | disp=out}}}} {{anchor|C10}} || 2<sup>−{{frac|9|3|4}}</sup> ≈  {{round|0.0011613351|4}}
|-
!''i''
| colspan=3| <math>\left(\alpha_A\cdot r^{i+1}\right) \times \left(\alpha_A\cdot r^{i}\right),</math> where <br> <math>\alpha_A = \sqrt[4]{2}\,\text{m}; r=\tfrac{1}{\sqrt{2}}</math>
| colspan=3| <math>\left(\alpha_B\cdot r^{i+1}\right) \times \left(\alpha_B\cdot r^{i}\right),</math> where <br> <math>\alpha_B = \sqrt{2}\,\text{m}; r=\tfrac{1}{\sqrt{2}}</math>
| colspan=3| <math>\left(\alpha_C\cdot r^{i+1}\right) \times \left(\alpha_C\cdot r^{i}\right),</math> where <br> <math>\alpha_C = \sqrt[8]{8}\,\text{m}; r=\tfrac{1}{\sqrt{2}}</math>
|}

The <math>\alpha</math> variables are the distinct first terms in the three [[geometric progression]]s of the same ''common ratio'' equal to the square root of two. Each of the three geometric progressions (corresponding to the three [[#ISO A|series A]], [[#ISO B|B]], and [[#ISO C|C]]) is formed by all possible paper dimensions (length and width) of the series arranged in decreasing order. This interesting arrangement of dimensions is also very useful—not only does it form a geometric progression with easy-to-remember formulae, but also each consecutive pair of values (like a sliding window of size 2) will automatically correspond to the dimensions of a standard paper format in the series.

The [[tolerances]] specified in the standard are

* ±1.5&nbsp;mm (0.06&nbsp;in) for dimensions up to 150&nbsp;mm (5.9&nbsp;in),
* ±2&nbsp;mm (0.08&nbsp;in) for lengths in the range 150 to 600&nbsp;mm (5.9 to 23.6 in) and
* ±3&nbsp;mm (0.12&nbsp;in) for any dimension above 600&nbsp;mm (23.6&nbsp;in).

{{anchor|DIN D|DIN 2A0|DIN 4A0|ISO 2A0|ISO 4A0|German extensions}}

=== Related regional sizes ===

==== German original ====

The German standard DIN 476 was published on 18 August 1922 and is the original specification of the [[#DIN A|A]], [[#DIN B|B]] and [[#DIN C|C sizes]]. In 1991, it was split into DIN 476-1 for the A and B formats and 476-2 for the C series. The former has been withdrawn in 2002 in favor of adopting the international standard as DIN EN ISO 216, but part 2 has been retained and was last updated in 2008.

The first and the second editions of DIN 476 from 1922 and 1925 also included a D series.

{| class="wikitable"
|+ DIN D series paper sizes in portrait view (with rounded inch values)
! Format
!colspan="2"| [[#DIN D|D series]]
|-
! Size
! mm × mm || inch × inch
|-
! 0
| {{size|771|1090}}
|-
! 1
| {{size|545|771}}
|-
! 2
| {{size|385|545}}
|-
! 3
| {{size|272|385}}
|-
! 4
| {{size|192|272}}
|-
! 5
| {{size|136|192}}
|-
! 6
| {{size|96|136}}
|-
! 7
| {{size|68|96}}
|-
! 8
| {{size|48|68}}
|}

The smallest formats in the original specifications for each series were A13, B13, C8, and D8. Sizes A11 through A13 were no longer listed in the 1930 edition, nor were B11 through B13. C9 and C10 were added in the 1976 revision for compatibility with photography sizes: C8 closely matches [[photo print sizes|6×9 photos]], and C9 and C10 closely match 7×7 and 5×5 [[diapositive|slides]], respectively.

{| class="wikitable"
|+ DIN 476:1922 tiny formats (with rounded inch values)
! Format !!colspan=2| A !!colspan=2| B
|-
! Size !! mm × mm || inch × inch !! mm × mm || inch × inch
|-
! 11
| {{size|18|26}}
| {{size|22|31}}
|-
! 12
| {{size|13|18}}
| {{size|15|22}}
|-
! 13
| {{size|9|13}}
| {{size|11|15}}
|}

DIN 476 provides for formats larger than A0, denoted by a prefix factor. In particular, it lists the formats 2A0 and 4A0, which are twice and four times the size of A0 respectively.
However, ISO 216:2007 notes 2A0 and 4A0 in the table of ''Main series of trimmed sizes'' (ISO A series) as well: "The rarely used sizes [2A0 and 4A0] which follow also belong to this series."

{| class="wikitable"
|+ DIN 476 overformats (with rounded inch values)
! Name !! mm × mm !! inch × inch
|-
! 4A0
| {{size|1682|2378}}
|-
! 2A0
| {{size|1189|1682}}
|}

DIN 476 also used to specify slightly tighter tolerances than ISO 216:

* ±1&nbsp;mm (0.04&nbsp;in) for dimensions up to 150&nbsp;mm (5.9&nbsp;in),
* ±1.5&nbsp;mm (0.06&nbsp;in) for lengths in the range 150&nbsp;mm to 600&nbsp;mm (5.9 to 23.6 in) and
* ±2&nbsp;mm (0.08&nbsp;in) for any dimension above 600&nbsp;mm (23.6&nbsp;in).

There used to be a standard, DIN 198, that was just a table of recommended A series formats for a number of business applications. The 1976 edition of this standard introduced a size '''{{frac|2|3}} A4''' {{resx|198 mm|210 mm}} and suggested it for some forms and slips.

{{anchor|SIS D|SIS E|SIS F|SIS G}}

==== Swedish extensions ====
[[File:Comparison SIS 014711 paper sizes.svg|thumb|200px|Comparison of ISO 216 and Swedish standard SIS 014711 paper sizes between A4 and A3 sizes]]

The Swedish standard [[Swedish Standards Institute|SIS]] 01 47 11<ref name="ss014711">{{cite web |title=Papper—Formatserier A-G |url=https://www.sis.se/en/produkter/standardization/information-sciences-publishing/documents-in-administration-commerce-and-industry/ss14711/ |work=Svensk standard SS 01 47 11 Utgåva 2 |at=Page 2 Figur 1 - Serieformaten exemplifierade |publisher=Swedish Standards Institute |access-date=25 December 2019 |archive-url=https://web.archive.org/web/20131101094445/http://www.sis.se/pappersteknik/pappersprodukter/ss-14711 |archive-date=1 November 2013 |url-status=live}}{{subscription required}}</ref> generalized the ISO system of [[#ISO A|A]], [[#ISO B|B]], and [[#ISO C|C]] formats by adding D, E, F, and G formats to it. Its D format sits between a B format and the next larger A format (just like C sits between A and the next larger B). The remaining formats fit in between all these formats, such that the [[bit-reversal_permutation#Example|sequence of formats]] A4, E4, C4, G4, B4, F4, D4, *H4, A3 is a [[geometric progression]], in which the dimensions grow by a factor <math>\sqrt[16]{2}</math> from one size to the next. However, this SIS standard does not define any size between a D format and the next larger A format (called *H in the previous example).

Of these additional formats, G5 (169 × 239&nbsp;mm) and E5 (155 × 220&nbsp;mm) are popular in Sweden and the Netherlands for printing dissertations,<ref>{{Cite web|url=http://ki.se/content/1/c6/05/90/62/Typography_en.pdf |publisher=Karolinska University Press |title=Typography and readability – a guideline |access-date=19 October 2012 |archive-url=https://web.archive.org/web/20131101001357/http://ki.se/content/1/c6/05/90/62/Typography_en.pdf |archive-date=1 November 2013}}</ref> but the other formats have not turned out to be particularly useful in practice. They have not been adopted internationally and the Swedish standard has been withdrawn.

The Swedish and [[#DIN D|German D series]] basically contain the same sizes but are offset by one, i.e. DIN D4 equals SIS D5 and so on.

{| class="wikitable"
|+ SIS 014711 formulas,<ref>{{cite web |url=http://home.comcast.net/~tamivox/dave/IntlPaper/index.html |archive-url=https://archive.today/20140701234154/http://home.comcast.net/~tamivox/dave/IntlPaper/index.html |url-status=dead |archive-date=1 July 2014 |author-first=Dave |author-last=Barber |title=International paper sizes. A, B, C and D series |date=8 May 2012}}</ref> including the missing step, series *H, between D and A,<br> 
<math display="inline">n = 0..10, r = \sqrt[16]{2}, s = \sqrt{\frac{1}{2}}</math>
|-
! Designation
! Shorter edge
! Longer edge
|-
! A''n''
| ''r''<sup>−4</sup> × ''s''<sup>''n''</sup>
| ''r''<sup>+4</sup> × ''s''<sup>''n''</sup>
|-
! E''n''
| ''r''<sup>−3</sup> × ''s''<sup>''n''</sup>
| ''r''<sup>+5</sup> × ''s''<sup>''n''</sup>
|-
! C''n''
| ''r''<sup>−2</sup> × ''s''<sup>''n''</sup>
| ''r''<sup>+6</sup> × ''s''<sup>''n''</sup>
|-
! G''n''
| ''r''<sup>−1</sup> × ''s''<sup>''n''</sup>
| ''r''<sup>+7</sup> × ''s''<sup>''n''</sup>
|-
! B''n''
| ''r''<sup> 0</sup> × ''s''<sup>''n''</sup>
| ''r''<sup>+8</sup> × ''s''<sup>''n''</sup>
|-
! F''n''
| ''r''<sup>+1</sup> × ''s''<sup>''n''</sup>
| ''r''<sup>+9</sup> × ''s''<sup>''n''</sup>
|-
! D''n''
| ''r''<sup>+2</sup> × ''s''<sup>''n''</sup>
| ''r''<sup>+10</sup> × ''s''<sup>''n''</sup>
|-
!title="not part of the Swedish standard"| *H''n''
| ''r''<sup>+3</sup> × ''s''<sup>''n''</sup>
| ''r''<sup>+11</sup> × ''s''<sup>''n''</sup>
|-
! A(''n''-1)
| ''r''<sup>+4</sup> × ''s''<sup>''n''</sup>
| ''r''<sup>+12</sup> × ''s''<sup>''n''</sup>
|}

{| class="wikitable"
|+ Swedish D through G series
! ''n'' !!style="display:none"|     A      !! '''E'''  !!style="display:none"|     C     !!  '''G'''  !!style="display:none"|     B     !!  '''F'''  !!  '''D'''  !!style="display:none"|    *H
|-
! 0 
|style="display:none"| 841 × 1189|| 878 × 1242||style="display:none"| 917 × 1297|| 958 × 1354||style="display:none"|1000 × 1414||1044 × 1477||1091 × 1542||style="display:none"|1139 × 1610
|-
! 1 
|style="display:none"| 595 × 841 || 621 × 878 ||style="display:none"| 648 × 917 || 677 × 958 ||style="display:none"| 707 × 1000|| 738 × 1044|| 771 × 1091||style="display:none"| 805 × 1139
|-
! 2 
|style="display:none"| 420 × 595 || 439 × 621 ||style="display:none"| 459 × 648 || 479 × 677 ||style="display:none"| 500 × 707 || 522 × 738 || 545 × 771 ||style="display:none"| 569 × 805
|-
! 3 
|style="display:none"| 297 × 420 || 310 × 439 ||style="display:none"| 324 × 459 || 339 × 479 ||style="display:none"| 354 × 500 || 369 × 522 || 386 × 545 ||style="display:none"| 403 × 569
|-
! 4 
|style="display:none"| 210 × 297 || 220 × 310 ||style="display:none"| 229 × 324 || 239 × 339 ||style="display:none"| 250 × 354 || 261 × 369 || 273 × 386 ||style="display:none"| 285 × 403
|-
! 5 
|style="display:none"| 149 × 210 || 155 × 220 ||style="display:none"| 162 × 229 || 169 × 239 ||style="display:none"| 177 × 250 || 185 × 261 || 193 × 273 ||style="display:none"| 201 × 285
|-
! 6 
|style="display:none"| 105 × 149 || 110 × 155 ||style="display:none"| 115 × 162 || 120 × 169 ||style="display:none"| 125 × 177 || 131 × 185 || 136 × 193 ||style="display:none"| 142 × 201
|-
! 7 
|style="display:none"|  74 × 105 ||  78 × 110 ||style="display:none"|  81 × 115 ||  85 × 120 ||style="display:none"|  88 × 125 ||  92 × 131 ||  96 × 136 ||style="display:none"| 101 × 142
|-
! 8 
|style="display:none"|  53 ×  74 ||  55 ×  78 ||style="display:none"|  57 ×  81 ||  60 ×  85 ||style="display:none"|  63 ×  88 ||  65 ×  92 ||  68 ×  96 ||style="display:none"|  71 × 101
|-
! 9 
|style="display:none"|  37 ×  53 ||  39 ×  55 ||style="display:none"|  41 ×  57 ||  42 ×  60 ||style="display:none"|  44 ×  63 ||  46 ×  65 ||  48 ×  68 ||style="display:none"|  50 ×  71
|-
!10 
|style="display:none"|  26 ×  37 ||  27 ×  39 ||style="display:none"|  29 ×  41 ||  30 ×  42 ||style="display:none"|  31 ×  44 ||  33 ×  46 ||  34 ×  48 ||style="display:none"|  36 ×  50
|}

{{anchor|JIS B}}{{anchor|Japanese B-series variant}}

==== Japanese variation ====

The Japanese standard [[Japanese Industrial Standards|JIS P 0138]] defines two main series of paper sizes. The JIS A-series is identical to the [[#ISO A|ISO A-series]] except that it has slightly different tolerances. The area of B-series paper is 1.5 times that of the corresponding A-paper (instead of the factor <math>\sqrt{2} = 1.414...</math> for the [[#ISO B|ISO B-series]]), so the length ratio is approximately 1.22 times the length of the corresponding A-series paper. The aspect ratio of the paper is the same as for the A-series paper. Both A- and B-series paper are widely available in Japan, [[Taiwan]] and China, and most photocopiers are loaded with at least A4 and either one of A3, B4, and B5 paper.

[[Cascading Style Sheets]] (CSS) only supports the most popular of the Japanese sizes, ''JIS-B4'' and ''JIS-B5''.<ref name="mozilla.org"/>

{| class="wikitable"
|+ JIS B series paper sizes (with rounded inch values)
! Size !! mm × mm || inch × inch
|-
! 0
| {{size|1030|1456}}
|-
! 1
| {{size|728|1030}}
|-
! 2
| {{size|515|728}} 
|-
! 3
| {{size|364|515}} 
|-
! 4
| {{size|257|364}} 
|-
! 5
| {{size|182|257}} 
|-
! 6
| {{size|128|182}} 
|-
! 7
| {{size|91|128}}
|-
! 8
| {{size|64|91}}
|-
! 9
| {{size|45|64}}
|-
! 10
| {{size|32|45}}
|-
! 11
| {{size|22|32}}
|-
! 12
| {{size|16|22}}
|}

{| class="wikitable"
|+ JIS P 0202 raw sizes (with rounded inch values)
! Size !! mm × mm || inch × inch ||title="aspect ratio"| AR || sun × sun
|-
!title="between ISO RA1 and SRA1"| A<!--列本判-->
| {{size|625|880|ar=on}} || {{resx|20.6|29}}
|-
!title="JIS B1 oversize"| B<!--列本判-->
| {{size|765|1085|ar=on}} || {{resx|25.25|35.8}}
|-
! Shiroku-ban (4-6)<!--四六判, duodecimo-->
| {{size|788|1091|ar=on}} || {{resx|26|36}}
|-
! Kiku-ban (Chrysanthemum)<!--菊判 -->
| {{size|636|939|ar=on}} || {{resx|21|31}}
|-
! Hattron <!--ハトロン判-->
| {{size|900|1200|ar=on}} || {{resx|29.7|39.6}}
|}

A popular size for books, dubbed AB, combines the shorter edges of A4 and B4. Another two with an aspect ratio approximating [[16:9]] are 20% narrower variants of A6 and B6, respectively, the latter resulting from cutting JIS B1 into {{resx|4|10}} sheets (thus "B40").

There are also a number of traditional paper sizes, which are now used mostly by printers. The most common of these old series is the [[#K|Shiroku-ban]] and the Kiku paper sizes.

{| class="wikitable"
|+ Other Japanese paper sizes (with rounded inch values){{qn|date=January 2020}}
! Size
! mm × mm || inch × inch !!title="aspect ratio"| AR !! sun × sun !! Notes
|-
! AB
| {{size|210|257|ar=on}}
| {{resx|6.93|8.48}} || {{resx|A4/A5|JIS B4/B5}}
|-
! B40
| {{size|103|182|ar=16:9}} || {{resx|3.4|6}}
| JIS B1 {{resx|{{frac|height|10}}|{{frac|width|4}}}}
|-
! 35
| {{size|84|148|ar=16:9}} || {{resx|2.77|4.88}} 
| trimmed {{resx|3|5}}<!--?-->
|-
!rowspan=4| Kiku-ban
| {{size|227|304|ar=on}} || {{resx|7.5|10}} <!--secondary variant according to Japanese Wikipedia, previously listed with 306 mm-->
|-
| {{size|218|304|ar=on}} || {{resx|7.2|10}} <!--[[:jp:菊判]]-->
|-
| {{size|152|227|ar=on}} || {{resx|5|7.5}} <!--secondary variant, previously listed with 151 mm-->
|-
| {{size|152|218|ar=on}} || {{resx|5|7.2}} <!--[[:jp:菊判]]-->
|}

{{anchor|GB/T 148}}

==== Chinese extensions ====

The Chinese standard GB/T 148–1997,<ref>{{Cite web |url=http://www.gb688.cn/bzgk/gb/newGbInfo?hcno=20746CFEE63514B24DD64A415CB65377 |title=国家标准 {{!}} GB/T 148-1997 |date=26 May 1997 |website=Standardization Administration of China |access-date=13 April 2017 |archive-url=https://web.archive.org/web/20170413154251/http://www.gb688.cn/bzgk/gb/newGbInfo?hcno=20746CFEE63514B24DD64A415CB65377 |archive-date=13 April 2017 |url-status=dead }}</ref> which replaced GB 148–1989, documents the standard ISO series, A and B, but adds a custom D series. This Chinese format originates from the [[Republic of China (1912–1949)]]. The D series is not identical to the German or Swedish D series. It does not strictly follow the same principles as ISO paper sizes: The aspect ratio is only very roughly <math>\sqrt{2}</math>. The short side of the size is always 4&nbsp;mm longer than the long side of the next smaller size. The long side of the size is always exactly &ndash; i.e. without further rounding &ndash; twice as long as the short side of the next smaller size.

{| class="wikitable"
|+ [[Standardization Administration of China|SAC]] paper sizes (with rounded inch values and raw sizes)
! Format
!colspan=2| D series
!rowspan=2 title="aspect ratio"| AR
!rowspan=2| Alias
!colspan=2| Untrimmed sizes
|-
! Size
! mm × mm || inch × inch
! mm × mm || inch × inch
|-
! 0
| {{size|764|1064}}
| 1.3927
| 1K
| {{size|780|1080}}
|-
! 1
| {{size|532|760}}
| 1.4286
| 2K
| {{size|540|780}}
|-
! 2
| {{size|380|528}}
| 1.3895
| 4K
| {{size|390|540}}
|-
! 3
| {{size|264|376}}
| 1.{{overline|4242}}
| 8K
| {{size|270|390}}
|-
! 4
| {{size|188|260}}
| 1.3830
| 16K
| {{size|195|270}}
|-
! 5
| {{size|130|184}}
| 1.4154
| 32K
| {{size|135|195}}
|-
! 6
| {{size|92|126}}
| 1.3696
| 64K
| {{size|97|135}}
|}

==== Indian variants ====
The ''Bureau of Indian Standards'' recommends the "ISO-A series" size of drawing sheet for engineering drawing works. The Bureau of Indian Standards specifies all the recommendations for engineering drawing sheets in its bulletin IS 10711: 2001.<ref>{{Cite book|url=https://law.resource.org/pub/in/bis/S01/is.sp.46.2003.pdf|title=SP 46 (2003): Engineering Drawing Practice for Schools and Colleges |publisher=Bureau of Indian Standards |isbn=81-7061-019-2 |date=Jul 2003 |url-status=live |archive-url=https://web.archive.org/web/20230909054902/https://law.resource.org/pub/in/bis/S01/is.sp.46.2003.pdf |archive-date= Sep 9, 2023 }}</ref>

The Bureau extended the ISO-A series with a '''Special Elongated Sizes''' (Second Choice). These sizes are achieved by increasing the shorter dimensions of a sheet of the ISO A series to lengths that are multiples of the shorter dimensions of the chosen basic sheet; in effect, all of the Indian elongated sizes emulate having several regular-size sheets joined on their long edge.

{| class="wikitable"
|+ IS Special Elongated Sizes (Second Choice) with rounded inch values
! Size !! mm × mm !! in × in !!title="aspect ratio"| AR
|-
! A3 x 3
| {{size|420|891|ar=on}} 
|-
! A3 x 4
| {{size|420|1189|ar=on}}
|-
! A4 x 3
| {{size|297|630|ar=on}}
|-
! A4 x 4
| {{size|297|841|ar=on}}
|-
! A4 x 5
| {{size|297|1051|ar=on}}
|}

There is also a '''Exceptional Elongated Sizes''' (Third Choice). These sizes are obtained by increasing the shorter dimensions of a sheet of the ISO-A series to lengths that are multiples of the shorter dimensions of the chosen basic sheet. These sizes are used when a very large or extra elongated sheet is needed.

{| class="wikitable"
|+ IS Exceptional Elongated Sizes (Third Choice) with rounded inch values
! Size !! mm × mm !! in × in !!title="aspect ratio"| AR
|-
! A0 x 2
| {{size|1189|1682|ar=2:√2}} 
|-
! A0 x 3
| {{size|1189|2523|ar=on}}
|-
! A1 x 3
| {{size|841|1783|ar=on}}
|-
! A1 x 4
| {{size|841|2378|ar=on}}
|-
! A2 x 3
| {{size|594|1261|ar=on}}
|-
! A2 x 4
| {{size|594|1682|ar=on}}
|-
! A2 x 5
| {{size|594|2102|ar=on}}
|-
! A3 x 5
| {{size|420|1486|ar=on}}
|-
! A3 x 6
| {{size|420|1783|ar=on}}
|-
! A3 x 7
| {{size|420|2080|ar=on}}
|-
! A4 x 6
| {{size|297|1261|ar=on}}
|-
! A4 x 7
| {{size|297|1471|ar=on}}
|-
! A4 x 8
| {{size|297|1682|ar=on}}
|-
! A4 x 9
| {{size|297|1892|ar=on}}
|}

{{anchor|OST 303}}{{anchor|OST 5115}}

==== Soviet variants ====

The first standard of paper size in the Soviet Union was OST 303 in 1926. Six years later, it was replaced by OST 5115 which generally followed DIN 476 principles, but used Cyrillic lowercase letters instead of Latin uppercase, had the second row shifted so that б<sub>0</sub> (B0) roughly corresponded to B1 and, more importantly, had slightly different sizes:<ref>{{Cite web |last=Митяев |first=К. Г. |date=1946 |title=Теория и практика архивного дела |trans-title=Theory and practice of archiving |url=http://www.spsl.nsc.ru/FullText/Книги/Уст.%20902%20М.678/Уст.%20902%20М.678.pdf |url-status=dead |archive-url=https://web.archive.org/web/20200208012944/http://www.spsl.nsc.ru/FullText/%D0%9A%D0%BD%D0%B8%D0%B3%D0%B8/%D0%A3%D1%81%D1%82.%20902%20%D0%9C.678/%D0%A3%D1%81%D1%82.%20902%20%D0%9C.678.pdf |archive-date=2020-02-08 |access-date=2022-07-15}}</ref>

{| class="wikitable"
|+ OST 5115 formats (1932)
! Format !!colspan=2| а (A) !!colspan=2| б (B) !!colspan=2| в (V, C)
|-
! Size 
! mm × mm !! inch × inch
! mm × mm !! inch × inch
! mm × mm !! inch × inch
|-
! 0
| {{size|814|1152}} || {{size|747|1056}} ||colspan=2|
|-
! 1
| {{size|576|814}}|| {{size|528|747}}|| {{size|628|888}}
|-
! 2
| {{size|407|576}}|| {{size|373|528}}|| {{size|444|628}}
|-
! 3
| {{size|288|407}}|| {{size|264|373}}|| {{size|314|444}}
|-
! 4
| {{size|203|288}}|| {{size|186|264}}|| {{size|222|314}}
|-
! 5
| {{size|144|203}}|| {{size|132|186}}|| {{size|157|222}}
|-
! 6
| {{size|101|144}}|| {{size|93|132}}|| {{size|111|157}}
|-
! 7
| {{size|72|101}}|| {{size|66|93}}|| {{size|78|111}}
|-
! 8
| {{size|50|72}}|| {{size|46|66}}|| {{size|55|78}}
|-
! 9
| {{size|36|50}}|| {{size|33|46}}|| {{size|39|55}}
|-
! 10
| {{size|25|36}}|| {{size|23|33}} ||colspan=2 rowspan=4|
|-
! 11
| {{size|18|25}}|| {{size|16|23}}
|-
! 12
| {{size|12|18}}|| {{size|11|16}}
|-
! 13
| {{size|9|12}} ||colspan=2|
|}

The general adaptation of ISO 216 in the Soviet Union, which replaced OST 5115, was GOST 9327. In its 1960 version, it lists formats down to A13, B12 and C8 and also specifies {{frac|1|2}}, {{frac|1|4}} and {{frac|1|8}} prefixes for halving the shorter side (repeatedly) for stripe formats, e.g. {{frac|1|2}}A4 = 105&nbsp;mm × 297&nbsp;mm.

[[File:Old Soviet standard for paper sizes.svg|thumb|A1, A2, A3, A4 and non-ISO sizes as GOST 3450-60 formats]]
A standard for technical drawings from 1960, GOST 3450,<ref>{{cite web |url=http://weldworld.ru/theory/cherchenie/formaty.html#link2 |title=Formaty |script-title=ru:Форматы |trans-title=Formats |website=Мир Сварки |language=ru |access-date=2 December 2017 |archive-url=https://web.archive.org/web/20171202203209/http://weldworld.ru/theory/cherchenie/formaty.html#link2 |archive-date=2 December 2017 |url-status=live}}</ref> introduces alternative numeric format designations to deal with very high or very wide sheets.
These 2-digit codes are based upon A4 = "11": The first digit is the factor the longer side (297&nbsp;mm) is multiplied by and the second digit is the one for the shorter side (210&nbsp;mm), so "24" is 2×297&nbsp;mm × 4×210&nbsp;mm = 594&nbsp;mm × 840&nbsp;mm.

{| class="wikitable"
|+ Soviet formats with multiplied shorter side (mm×mm)
|-
| ''n''
! (×1) !! ×2 !! ×3 !! ×4 !! ×5 !! ×6
|-
!title="4·4n"| 5
|title="4·4"| = A0 ||title="4·8"| = 2A0||title="4·12"|2523 × 1189||title="4·16"|3364 × 1189||title="4·20"|4204 × 1189 ||title="4·24"|5045 × 1189
|-
!title="2n·4"| 4
|title="2·4"| = A1 ||title="4·4"| = A0 ||title="6·4"|1784 × 841 ||title="8·4"|2378 × 841 ||title="10·4"|2973 × 841 ||title="12·4"|3568 × 841
|-
!title="2·2n"| 3
|title="2·2"| = A2 ||title="2·4"| = A1  ||title="2·6"|1261 × 595 ||title="2·8"|1682 × 595 ||title="2·10"|2102 × 595 ||title="2·12"|2523 × 595
|-
!title="n·2"|  2 
|title="1·2"| = A3 ||title="2·2"| = A2  ||title="3·2"| 892 × 420 ||title="4·2"|1189 × 420 ||title="5·2"|1487 × 420 ||title="6·2"|1784 × 420
|-
!title="1·n"| 1
|title="1·1"| = A4 ||title="1·2"| = A3  ||title="1·3"| 631 × 297 ||title="1·4"| 841 × 297 ||title="1·5"|1051 × 297 ||title="1·6"|1261 × 297
|-
!title="{{frac|1|2}}n·1"| 0
|title="{{frac|1|2}}·1"| = A5 ||title="1·1"| = A4  ||title="{{frac|1|1|2}}·1"|446 × 210 ||title="2·1"| 595 × 210 ||title="{{frac|2|1|2}}·1"| 743 × 210 ||title="3·1"| 892 × 210
|}

[[File:GOST 2301-68.svg|thumb|A2, A3, A4 and some derived non-ISO sizes as GOST 2301-68 formats]]
GOST 3450 from 1960 was replaced by ESKD GOST 2301 in 1968,<ref>{{cite web |url=http://graph.power.nstu.ru/wolchin/umm/eskd/eskd/GOST/2_301.htm |script-title=ru:Форматы (ЕСКД ГОСТ 2.301-68) |title=Formaty (ESKD GOST 2.301-68) |trans-title=Formats |website=Единая Система Конструкторской Документации |language=ru |access-date=2 December 2017 |archive-url=https://web.archive.org/web/20161201015706/http://graph.power.nstu.ru/wolchin/umm/eskd/eskd/GOST/2_301.htm |archive-date=1 December 2016 |url-status=live}}</ref> but the numeric designations remained in popular use much longer.
The new designations were not purely numeric but consisted of the ISO label followed by an 'x', or possibly the multiplication sign '×', and the factor, e.g. DIN 2A0 = GOST A0×2, but DIN 4A0 ≠ GOST A0×4, also listed are: A0×3, A1×3, A1×4, A2×3–A2×5, A3×3–A3×7, A4×3–A4×9. The formats ...×1 and ...×2 usually would be aliases for existing formats.

{{anchor|ISO 5457}}

=== Elongated sizes ===

ISO 5457, last updated in 1999,<ref name="iso5457">{{Cite web|url=https://www.iso.org/standard/29017.html |title=ISO 5457:1999|website=ISO}}</ref> introduces elongated sizes that are formed by a combination of the dimensions of the short side of an A-size (e.g. A2) with the dimensions of the long side of another larger A-size (e.g. A0). The result is a new size, for example with the abbreviation A2.0 we would have a {{resx|420|1189}} mm size.
[[File:ISO 5457 elongated paper sizes.svg|alt=elongated ISO paper sizes|thumb|elongated paper sizes schema]]
{| class="wikitable"
|+ ISO 5457 elongated paper sizes
! Size !! Short edge !! Long edge !! mm × mm !! in × in !!title="aspect ratio"| AR
|-
! A1.0
| A1/A2 || A0
| {{size|594|1189|ar=2:1}}
|-
! A2.0
|rowspan=2| A2/A3 || A0
| {{size|420|1189|ar=2√2:1}}
|-
! A2.1
| A1/A0
| {{size|420|841|ar=2:1}}
|-
! A3.0
|rowspan=3| A3/A4 || A0
| {{size|297|1189|ar=4:1}}
|-
! A3.1
| A1/A0
| {{size|297|841|ar=2√2:1}}
|-
! A3.2
| A2/A1
| {{size|297|594|ar=2:1}}
|}

These drawing paper sizes have been adopted by [[ANSI/ASME Y14.1|ANSI/ASME Y14.1M]] for use in the United States, alongside A0 through A4 and alongside inch-based sizes.

=== International envelope and insert sizes ===
{{main|Envelope#Sizes}}

{| class="wikitable"
|+ Common folded or cut sizes of ISO paper: stripe formats and inserts
|-
! Name
! mm × mm !! inch × inch !!title="aspect ratio"| AR
! Notes
|-
! {{frac|3}}A4
| {{size|99|210|ar=on}}
| common flyer or stripe size
|-
! ''unnamed''
| {{size|105|210|ar=on}}
| standard folded size of German letters
|}

[[File:DIN_5008,_Form_A.svg|thumb|DIN 5008 Form A]]
DIN 5008 (previously DIN 676) prescribes, among many other things, two variants, A and B, for the location of the address field on the first page of a business letter and how to fold the A4 sheet accordingly, so the only part visible of the main content is the subject line.

{| class="wikitable"
|+ Common envelopes for ISO paper, that are not simple C-series and B-series formats
|-
! Name
! mm × mm !! inch × inch !!title="aspect ratio"| AR
! Content
! Notes
|-
! DL
| {{size|110|220|ar=on}}
|rowspan=3| {{frac|3}}A4, DIN 5008 A and B
| ''designated long'', "DIN lang" ([[Deutsches Institut für Normung|DIN]] long); sometimes erroneously instead called "DLE", apparently for ''envelope''; exactly matches Swedish SIS E6/E5 (E6: {{resx|110 mm|155 mm}}, E5: {{resx|155 mm|220 mm}}); envelope #5 in China, Chou/N 6 in Japan; fits well enclosed in C6/C5 for the purpose of e.g. reply mail
|-
! C6/C5
| {{size|114|229|ar=2}}
| common edge of C6 and C5 is 161&nbsp;mm; 
also known as "Postfix", "DL+" or "DL Max", but those terms are not standardized
|-
! Italian 
| {{size|110|230|ar=2.1}}
| centimeter-rounded C6/C5 or slightly wider DL
|-
! C7/C6 
| {{size|81|162|ar=on}}
| {{frac|3}}A5
| common edge of C7 and C6 is 114&nbsp;mm 
|-
! B6/C4 
| {{size|125|324|ar=2.6}}
| 
| B6 is {{resx|125 mm|176 mm}}, C4 is {{resx|229 mm|324 mm}}
|-
! Invite
| {{size|220|220|ar=on}}
| square card with edge of A4 and A5, 210&nbsp;mm
| 
|-
! DIN E4
| {{size|280|400|ar=on}}
| 
| listed in DIN 476–2, but not part of a series proper; SIS E4 is {{resx|220 mm|310 mm}}
|}

{{anchor|ISO 217}}{{anchor|ISO 2784}}

=== International raw sizes ===

{| class="wikitable"
|+ ISO 217 raw and ISO 5457 untrimmed sheet sizes
|-
! raw
! mm × mm !! inch × inch
! special raw
! mm × mm !! inch × inch
! untrimmed
! mm × mm !! inch × inch
! trimmed
! mm × mm !! inch × inch
<!--! drawing area-->
! mm × mm !! inch × inch
|-
! RA0
| {{size|860|1220|p=4}}
! SRA0
| {{size|900|1280|p=4}}
! A0U
| {{size|880|1230|p=4}}
! A0T
| {{size|841|1189|p=4}}
| {{size|821|1159|p=4}}
|-
! RA1
| {{size|610|860|p=4}}
! SRA1
| {{size|640|900|p=4}}
! A1U
| {{size|625|880|p=4}}
! A1T
| {{size|594|841|p=4}}
| {{size|574|811|p=4}}
|-
! RA2
| {{size|430|610|p=4}}
! SRA2
| {{size|450|640|p=4}}
! A2U
| {{size|450|625|p=4}}
! A2T
| {{size|420|594|p=4}}
| {{size|400|564|p=4}}
|-
! RA3
| {{size|305|430|p=4}}
! SRA3
| {{size|320|450|p=4}}
! A3U
| {{size|330|450|p=4}}
! A3T
| {{size|297|420|p=4}}
| {{size|277|390|p=4}}
|-
! {{visible anchor|RA4}}
| {{size|215|305|p=4}}
! SRA4
| {{size|225|320|p=4}}
! A4U
| {{size|240|330|p=4}}
! A4T
| {{size|210|297|p=4}} 
| {{size|180|277|p=4}}
|}

ISO 5457 specifies drawing paper sizes with a trimmed size equal to the A series sizes from A4 upward. The untrimmed sizes are 3 to 4&nbsp;cm larger and rounded to the nearest centimetre. A0 through A3 are used in landscape orientation, while A4 is used in portrait orientation. Designations for preprinted drawing paper include the base sizes and a suffix, either ''T'' for trimmed or ''U'' for untrimmed sheets.

The withdrawn standard ISO 2784 did specify sizes of continuous, fan-fold forms based upon whole inches as was common for paper in continuous lengths in automatic data processing (ADP) equipment. Specifically, 12 inches (304.8&nbsp;mm) were considered an untrimmed variant of the A4 height of 297&nbsp;mm.

{| class="wikitable"
|+ ISO 2784:1974 correspondence for continuous ADP paper
!rowspan=2| Size 
!colspan=3| Acceptable equivalent 
!colspan=3| Direct equivalent 
! Exact size
!colspan=2| Gross size 
|-
! inch × inch !! mm × mm !!title="aspect ratio"| AR
! inch × inch !! mm × mm !!title="aspect ratio"| AR
! mm × mm
! mm × mm !! inch × inch
|-
! A4
| {{size|8|12|in|mm|f=4|ar=on}} || {{size|8+1/3|11+2/3|in|mm|f=4|ar=on}} || {{resx|210|297}} ||title="gross width for A3 is 450 mm, intermediate gross widths of 375 mm and 400 mm have no ISO 216 equivalent" {{size|250|340|p=10}}
|-
! A5
| {{size|6|8|in|mm|f=4|ar=on}} || {{size|5+5/6|8+1/3|in|mm|f=4|ar=on}} || {{resx|148|210}} || {{size|180|250|p=10}}
|-
! A6
| {{size|4|6|in|mm|f=4|ar=on}} || {{size|4+1/6|5+5/6|in|mm|f=4|ar=on}} || {{resx|105|148}} || {{n/a}} || {{n/a}}
|-
! A7
| {{size|3|4|in|mm|f=4|ar=on}} || {{n/a}} || {{n/a}} || {{n/a}} || {{resx|74|105}} || {{n/a}} || {{n/a}}
|}

== Transitional paper sizes ==

=== PA4 or L4 ===

{| class="wikitable floatright"
|+ Hypothetical PA4-based series
! Name
! mm × mm !! inch × inch !!title="aspect ratio"| AR
|-
! PA0
| {{size|840|1120|p=8|ar=on}}
|-
! PA1
| {{size|560|840|p=8|ar=on}}
|-
! PA2
| {{size|420|560|p=8|ar=on}}
|-
! PA3
| {{size|280|420|p=8|ar=on}}
|- style="font-weight: bolder"|
! PA4
| {{size|210|280|p=8|ar=on}}
|-
! PA5
| {{size|140|210|p=8|ar=on}}
|-
! PA6
| {{size|105|140|p=8|ar=on}}
|-
! PA7
| {{size|70|105|p=8|ar=on}}
|-
! PA8
| {{size|52|70|p=8|ar=on}}
|-
! PA9
| {{size|35|52|p=8|ar=on}}
|-
! PA10
| {{size|26|35|p=8|ar=on}}
|}

A transitional size called '''PA4''' ({{convert|210|×|280|mm|inch|2|abbr=on|disp=or}}), sometimes dubbed '''L4''', was proposed for inclusion into the ISO 216 standard in 1975. It has the height of Canadian P4 paper (215&nbsp;mm&nbsp;× 280&nbsp;mm, about {{frac|8|1|2}}&nbsp;in&nbsp;× 11&nbsp;in) and the width of international A4 paper ({{convert|210|×|297|mm|inch|2|abbr=on|disp=or}}), i.e. it uses the smaller value among the two for each side. The table shows how this format can be generalized into an entire format series.

The PA formats did not end up in ISO 216, because the committee decided that the set of standardized paper formats should be kept to the minimum necessary.{{citation needed|date=December 2016}} However, PA4 remains of practical use today. In [[landscape format|landscape]] orientation, it has the same 4:3 aspect ratio as the displays of traditional TV sets, some [[computer displays]] (e.g. the [[iPad]]) and [[data projector]]s. PA4, with appropriate [[margin (typography)|margin]]s is, therefore, a good choice as the format of presentation slides.

As a compromise between the two most popular paper sizes globally, PA4 is used today by many international magazines, because it can be printed easily on equipment designed for either A4 or US Letter. That means (in practice) it has turned out to be not so much a paper size as a page format. Apple, for instance, requires this format for digital music album booklets.<ref>{{cite web |url=https://help.apple.com/itc/videoaudioassetguide/#/itc585697a99 |title=Music Digital Booklet Profile | website=iTunes Video and Audio Asset Guide |author=Apple iTunes Store |date=2019}}</ref>

The size 210&nbsp;mm × 280&nbsp;mm was documented in the Canadian standard CAN2-200.2-M79 "Common Image Area for Paper Sizes P4 and A4".<ref>{{cite web |url=http://www.scc.ca/en/standardsdb/standards/2464 |title=CAN2-200.2-M79: "Common Image Area for Paper Sizes P4 and A4" |archive-url=https://web.archive.org/web/20170907123539/http://www.scc.ca/en/standardsdb/standards/2464 |archive-date=7 September 2017 |date=1 April 1979}} (NB. Withdrawn 1 March 2012.)</ref>

{{anchor|Paper size F4}}

=== F4 ===
{{see also|Foolscap folio#F4}}
{| class="wikitable floatright"
|+ Hypothetical F4-based series
|-
! Name
! mm × mm !! inch × inch !!title="aspect ratio"| AR
|-
! F0
| {{size|841|1321|p=8|ar=on}}
|-
! F1
| {{size|660|841|p=8|ar=on}}
|-
! F2
| {{size|420|660|p=8|ar=on}}
|-
! F3
| {{size|330|420|p=8|ar=on}}
|- style="font-weight: bolder"|
! F4
| {{size|210|330|p=8|ar=on}}
|-
! F5
| {{size|165|210|p=8|ar=on}}
|-
! F6
| {{size|105|165|p=8|ar=on}}
|-
! F7
| {{size|82|105|p=8|ar=on}}
|-
! F8
| {{size|52|82|p=8|ar=on}}
|-
! F9
| {{size|41|52|p=8|ar=on}}
|-
! F10
| {{size|26|41|p=8|ar=on}}
|}
A non-standard '''F4''' paper size is common in Southeast Asia. It is a transitional size with the shorter side of ISO A4 (210&nbsp;mm, {{frac|8|1|4}} inch) and the longer side of British ''Foolscap'' (13-inch, 330&nbsp;mm). ISO A4 is exactly 90% the height of F4.
This size is sometimes also known as [[#Foolscap|(metric) 'foolscap' or 'folio']]. 

In some countries, the narrow side of F4 is slightly broader: 8.5 inches (216 mm) or 215 mm. It is then equivalent to <!--one variant of--> the US ''Government Legal'' and ''Foolscap Folio'' sizes.
In Indonesia, where it is the legally-mandated paper size for use in the printing of [[law of Indonesia|national legislation]], it is sometimes called ''Folio'' or ''HVS'' (from {{langx|nl|houtvrij schrijfpapier}}, "[[wood-free paper|wood-free]] writing paper"). 
In Philippines, it is commonly called ''long bond'' as opposed to ''short bond'' which refers to the US Letter paper size.

A sheet of F4 can be cut from a sheet of SRA4 with very little wastage. The size is also smaller than its [[#Swedish extensions|Swedish equivalent]] SIS F4 at 239&nbsp;mm × 338&nbsp;mm.

=== Weltformat ===

The '''Weltformat''' (''world format'') was developed by German chemist [[Wilhelm Ostwald]] in 1911 as part of [[Die Brücke (institute)|Die Brücke]], around the same time DIN 476 was first discussed. It shares the same design primitives, especially the aspect ratio, but is based upon 1 cm as the short edge of the smallest size. Sizes were designated by roman numerals. 
The result, for the fourth through fourteenth size, is close to the DIN/ISO C series. 
<ref>{{cite news|author=Wilhelm Ostwald|title=Die Weltformate: I. Für Drucksachen|url=https://archive.org/details/DieWeltformate|publisher=Seybold|location=Ansbach|oclc=255038683|newspaper=[[Börsenblatt für den Deutschen Buchhandel]]|date=18 October 1911|issue=243|page= 12330}}</ref>

<ref>{{cite book|author=Karl Wilhelm Bührer|title=Raumnot und Weltformat: Schriften über Die Brücke|volume=Band 2|publisher=Seybold|location=München / Ansbach |year=1912|oclc=253384402}}</ref>

{| class="wikitable" 
|+ Original world format sizes with equivalent C-series format
|-
! Weltformat 
! mm × mm !! inch × inch 
! DIN 
|-
|I ||{{size|10|14|p=8}}|| 
|-
|II ||{{size|14|20|p=8}}|| 
|-
|III ||{{size|20|28|p=8}}|| 
|-
|IV ||{{size|28|40|p=8}}|| C10
|- 
|V ||{{size|40|57|p=8}}|| C9
|- 
|VI ||{{size|57|80|p=8}}|| C8
|- 
|VII ||{{size|80|113|p=8}}|| C7
|-
|VIII ||{{size|113|160|p=8}}|| C6
|-
|IX ||{{size|160|226|p=8}}|| C5
|-
|X ||{{size|226|320|p=8}}|| C4
|-
|XI||{{size|320|453|p=8}}|| C3
|- 
|XII ||{{size|453|640|p=8}}|| C2
|-
|XIII ||{{size|640|905|p=8}}|| C1
|- style="font-weight: bolder"|
|XIV ||{{size|905|1280|p=8}}|| C0
|-
|XV ||{{size|1280|1810|p=8}}|| 
|-
|XVI ||{{size|1810|2560|p=8}}|| 
|}

The sizes have been used for some print products in the early 20th century in central Europe but got replaced by DIN sizes almost entirely. However, it was successfully adopted from 1913 onwards for posters and placards in Switzerland. Even today, the default size for posters in Swiss advertisements, F4, is colloquially known as ''Weltformat'', although it measures 895 mm × 1280 mm, i.e. 1 cm less than size XIV. <ref name="APG">[https://www.apgsga.ch/en/templates-and-specifications/ APG|SGA: Templates and specifications]</ref> This  poster size goes alongside F12 "Breitformat" 2685 mm × 1280 mm (3 × F4) and F24 "Großformat" 2685 mm × 2560 mm (2 × 3 × F4, ) as well as F200 "Cityformat" 1165 mm × 1700 mm. 

=== A0a ===

Although the movement is towards the international standard metric paper sizes, on the way there from the traditional ones there has been at least one new size just a little larger than that used internationally.

British architects and industrial designers once used a size called "Antiquarian", {{convert|31|×|53|inch|mm|0|abbr=on}}, as listed [[#Traditional inch-based paper sizes|above]], but given in the ''New Metric Handbook'' (Tutt & Adler 1981) as {{convert|813|×|1372|mm|inch|0|abbr=on}} for board size. This is a little larger than ISO A0, 841&nbsp;mm × 1189&nbsp;mm. So for a short time, a size called '''A0a''' of {{convert|1000|×|1370|mm|inch|1|abbr=on}} was used in Britain, which is actually just a slightly shorter version of ISO B0 at 1414&nbsp;mm.

=== Pliego ===

{| class="wikitable floatright"
|+ Colombian metric paper sizes <ref>{{cite book |last1=Consuegra |first1=David |title=En busca del cuadrado |date=1992 |publisher=Editorial Universidad Nacional de Colombia |location=Bogotá |isbn=9789581700882 |pages=84–85 |url=https://books.google.com/books?id=CWTijWVrt3sC&pg=PA84 |access-date=19 April 2023}}</ref>
! Size
! mm × mm !! inch × inch !!title="aspect ratio"| AR
|-
! Pliego
| {{size|700|1000|p=4|ar=on}}
|-
! {{frac|2}} pliego
| {{size|500|700|p=4|ar=on}}
|-
! {{frac|4}} pliego
| {{size|350|500|p=4|ar=on}}
|-
! {{frac|8}} pliego
| {{size|250|350|p=4|ar=on}}
|}

The most common paper sizes used for commercial and industrial printing in Colombia<!-- other South-American countries as well? --> are based upon a size referred to as ''pliego'' that is ISO B1 (707&nbsp;mm × 1000&nbsp;mm) cut to full decimetres. Smaller sizes are derived by halving as usual and just get a [[vulgar fraction]] prefix: ''{{frac|2}} pliego'' and ''{{frac|4}} pliego''.

=== K ===
{{anchor|8K}}{{anchor|16K}}{{anchor|East-Asian sizes}}{{anchor|Shirokoban}}{{anchor|Chrysanthemum}}
{{refimprove|section|reason=Good sources are rare, especially in English.|date=May 2021}}

In East Asia, i.e. Japan, Taiwan, and China in particular, there is a number of similar paper sizes in common use for book-making and other purposes. 
Confusingly, a single designation is often used with slightly different edge measures: The base sheet is labeled '''1K''' (or {{lang|zh|1开}}, where ''K'' stands for {{zh|s=开本|l=[[folio]]|p=kāiběn}}; or {{Lang|ja|1切/1取}} in Japanese); all smaller sizes derived by halving have the power of two number, ''i'' = 2<sup>''n''</sup>, in front of the uppercase letter ''K''. The number in ISO designations, in contrast, is the exponent ''n'' that would yield the number of sheets cut from the base sizes.

The sizes of such folios depend on the base sheet. Pre-metric standards include:

* The imperial 菊判 (''kiku-ban''), named after the ''[[Chrysanthemum]]'' watermark on imperial paper, measuring 636mm × 939mm.
* The four-by-six 四六判 ''shi-roku-ban'' ('''4×6''' or '''4/6'''), where the final size at 32K was measured 4 by 6 [[cun (unit)|sun]] in [[Japanese units of measurement|Japan]], c. {{resx|121|181}} mm, or slightly more, {{resx|127 or 130|188}} mm i.e. {{resx|4.2 or 4.3|6.2}} sun.
** In Taiwan, the traditional base size 1K inherited from Japan is sometimes quoted as measuring {{resx|31|43}} inches exactly, which is off by c. 1 millimeter from the commonly quoted metric base size of {{resx|788|1091}} mm, which is directly derived from {{resx|26|36}} [[cun (unit)|''sun'']] or {{resx|2.6|3.6}} [[shaku (unit)|''shaku'']].
* The three-by-five 三五判 ('''3×5''' or '''3/5'''), where the final size at 32K is slightly less than 3 by 5 sun, often given as {{resx|84|148}} mm which would be c. {{resx|2.8|4.9}} ''sun''.

The 4/6 standard has given rise to newer metric book-size standards, including:

* The modern Japanese size for books, simply labeled ''B'' and is specified as {{resx|765|1085}} millimeters. It is not directly related to the similar [[#Japanese alternative|JIS B series]], where B1 is slightly smaller.
* The Chinese [[#Chinese extensions|SAC D series]].
{{Cleanup section|reason=Table is overly focused on 4/6 and similar sizes. Makes for a "uniform" comparison, but is not exactly right.|date=August 2021}}
{| class="wikitable"
|+ Traditional East-Asian ''Kai'' or 2<sup>''n''</sup>K paper sizes with comparable modern sizes, all in (mm × mm)
! || colspan="2" | 4/6|| colspan="2" rowspan="2" | Taiwanese finishes (trimmed 4/6)	|| rowspan="2" | Japan Kai	
! colspan="2" rowspan="2" |Japanese finishes|| rowspan="2" | JIS B	|| colspan="2" rowspan="2" | JIS P 0138	|| colspan="3" | SAC	
|-
!
!shaku-based 
!inch-based 
!
!trimmed
!untrimmed
|----
! 1K
| 788 × 1091	|| 787 × 1092	|| 758 × 1060	|| 760 × 1040	|| {{n/a}}	|| {{n/a}}	|| {{n/a}}	|| title="B" |  765 × 1085
! B1
| 728 × 1030
! D0
| 764 × 1064	|| 780 × 1080
|----
! 2K
| 545 × 788	|| 546 × 787	|| 530 × 758	|| 520 × 760	|| {{n/a}}	|| {{n/a}}	|| {{n/a}}	|| (542 × 765)
! B2
| 515 × 728
! D1
| 532 × 760	|| 540 × 780
|----
! 4K
| 394 × 545	|| 394 × 546	|| 379 × 530	|| 380 × 520	|| {{n/a}}	|| {{n/a}}	|| {{n/a}}	|| (382 × 542)
! B3
| 364 × 515
! D2
| 380 × 532	|| 390 × 540
|----
! 8K
| 272 × 394	|| 273 × 394	|| 265 × 379	|| 260 × 380	|| title="Pa Kai" | 267 × 389	|| title="Dai Pa Kai" | 275 × 395	|| 264 × 379	|| (271 × 382)
! B4
| 257 × 364
! D3
| 264 × 376	|| 270 × 390
|----
! 16K
| 197 × 272	|| 197 × 273	|| 189 × 265	|| 190 × 260	|| {{n/a}}	|| title="Juuro Ku Kai" | 198 × 275	|| 189 × 262	|| (191 × 271)
! B5
| title="AB is 210 × 257, from ISO A4" | 182 × 257
! D4
| 188 × 260	|| 195 × 270
|----
! title="4/6" | 32K
| 136 × 197	|| 137 × 197	|| 132 × 189	|| 130 × 190	|| title="4/6: 4.3 × 6.2 sun" | 130 × 188	|| {{n/a}}	|| title="Shirokoban, 4/6: 4.2 × 6.2 sun" | 127 × 188	|| (135 × 191)
! B6
| title="B40 is 103 × 182" | 128 × 182
! D5
| 130 × 184	|| 135 × 195
|----
! 64K
|  98 × 136	||  98 × 137	||  94 × 132	||  95 × 130	|| {{n/a}}	|| {{n/a}}	|| {{n/a}}	|| {{n/a}}
! B7
|  91 × 128
! D6
|  92 × 130	||  97 × 135
|----
! 128K
| colspan="2" |  68 ×  98	||  66 ×  94	||  65 ×  95	|| {{n/a}}	|| {{n/a}}	|| {{n/a}}	|| {{n/a}}
! B8
|  64 ×  91	|| {{n/a}}	|| (65 × 92)	|| (67 × 97)
|}
<!--
{| class="wikitable"
|+ Traditional East-Asian ''Chrysanthemum'' or 2<sup>''n''</sup>K paper sizes
! 	|| sun × sun || inch × inch
|----
! 1K
| 24 × 32	|| 31 × 43
|----
! 2K
| 16 × 24	|| {{frac|21|1|2}} × 31
|----
! 4K
| 12 × 16	|| {{frac|15|1|2}} × {{frac|21|1|2}}
|----
! 8K
| 8 × 12	|| {{frac|10|3|4}} × {{frac|15|1|2}}
|----
! 16K
| 6 × 8	|| {{frac|7|1|4}} × {{frac|10|3|4}}
|----
! 32K
| 4 × 6	|| {{frac|5|3|8}} × {{frac|7|1|4}}
|----
! 64K
| 3 × 4	|| {{frac|3|5|8}} × {{frac|5|3|8}}
|----
! 128K
| 2 × 3	|| {{frac|2|11|16}} × {{frac|3|5|8}}
|}
-->

== North American paper sizes ==
{{anchor|Loose sizes}}

=== Inch-based loose sizes ===
{| class="wikitable floatright"
|+ American loose paper sizes<ref name="PWG"/><!--Spanish names in ''italics'', most important sizes in bold face from {{rh}}-->
!style="max-width:14ch"| Size
! inch × inch || mm × mm ||title="aspect ratio"| AR
|-
!{{rh}}| [[Ledger]]<ref name="PPD"/>
| {{size|17|11|in|mm|ar=on}}
|-
!{{rh2}} title="S12R photo print"| Tabloid Extra<!--PWG 5101.1-->
| {{size|12|18|in|mm|ar=on}}
|-
!{{rh2}}| European EDP <!--PWG 5101.1-->
| {{size|12|14|in|mm|ar=on}}
|-
!{{rh}}| Tabloid
| {{size|11|17|in|mm|ar=on}}
|-
!{{rh2}}| {{resx|11|15}}<!--PWG 5101.1-->
| {{size|11|15|in|mm|ar=on}}
|-
!{{rh2}}| [[Continuous stationery|Fanfold]] <!--PWG 5101.1-->
| {{size|11|14+7/8|in|mm|ar=on}}
|-
!{{rh2}} title="11R photo print"| EDP <!--PWG 5101.1-->
| {{size|11|14|in|mm|ar=on}}
|-
!{{rh2}}| {{resx|11|12}}<!--PWG 5101.1-->
| {{size|11|12|in|mm|ar=on}}
|-
!{{rh2}}| {{resx|10|14}}<!--PWG 5101.1-->
| {{size|10|14|in|mm|ar=on}}
|-
!{{rh2}}| {{resx|10|13}}<!--PWG 5101.1-->
| {{size|10|13|in|mm|ar=on}}
|-
!{{rh2}}| {{resx|10|11}}<!--PWG 5101.1-->
| {{size|10|11|in|mm|ar=on}}
|-
!{{rh2}}| Legal Extra
| {{size|9+1/2|15|in|mm|ar=on}}
|-
!{{rh2}} title="one of the standard ISO 1008 photo print sizes"| Letter Extra <!--PWG 5101.1-->
| {{size|9+1/2|12|in|mm|ar=on}}
|-
!{{rh2}} title="old US alias: Quarto"| Letter Tab <!--PWG 5101.1-->
| {{size|9|11|in|mm|ar=on}}
|-
!{{rh}}| Legal
| {{size|8+1/2|14|in|mm|ar=on}}
|-
!{{rh2}}| [[Foolscap folio]] <!--PWG 5101.1--> <!--''Oficio''{{qn}}, ''Imperial''{{qn}}-->
| {{size|8+1/2|13+1/2|in|mm|ar=on}}
|-
!{{rh2}}| [[Foolscap folio#Oficio|''Oficio'']] <!--PWG 5101.1-->
| {{size|8+1/2|13+2/5|in|mm|ar=on}}
|-
!{{rh2}} title="British alias: Foolscap (Folio)"| Government Legal;<ref>{{Cite web|url=https://mainthebest.com/sizes/government-legal-size/|title=Government Legal Size|website=mainthebest}}</ref> [[#F4|Foolscap]]<ref name="PWG"/><!--PWG 5101.1-->
| {{size|8+1/2|13|in|mm|ar=on}}
|-
!{{rh2}}| Letter Plus <!--PWG 5101.1: 12.69-inch, perhaps 215 mm @ 2:3, i.e. 322.5 mm -->
| {{size|8+1/2|12+2/3|in|mm|ar=on}}
|-
!{{rh2}}| [[#RA4|European Fanfold]]
| {{size|8+1/2|12|in|mm|ar=on}}
|-
!{{rh}} title="Spanish: carta"| [[Letter (paper size)|Letter]]
| {{size|8+1/2|11|in|mm|ar=on}}
|-
!{{rh2}}| ''Quarto'' <!--PWG 5101.1: 10.83-inch-->
| {{size|8+1/2|10+5/6|in|mm|ar=on}}
|-
!{{rh2}}| Government Legal<ref name="PWG"/><!--PWG 5101.1 – this may be a mistake in the printer standard--> (Foolscap Folio)
| {{size|8|13|in|mm|ar=on}}
|-
!{{rh2}}| [[#Demitab|Demitab]] (Government Letter)
| {{size|8|10+1/2|in|mm|ar=on}}
|-
!{{rh2}} title="old British alias: (Copy Draught) Quarto; 8R or 6P photo print"| Government Letter<!--PWG 5101.1-->
| {{size|8|10|in|mm|ar=on}}
|-
!{{rh2}} title="old US alias: Monarch"| Executive<!--PWG 5101.1-->
| {{size|7+1/4|10+1/2|in|mm|ar=on}}
|-
!{{rh2}} title="old British alias: Imperial"| {{resx|7|9}}<!--PWG 5101.1-->
| {{size|7|9|in|mm|ar=on}}
|-
!{{rh2}}| Memo, Statement, Mini, Invoice<!--PWG 5101.1-->;<br> Stationery, Half Letter
| {{size|5+1/2|8+1/2|in|mm|ar=on}}
|-
!{{rh2}}| Junior Legal
| {{size|5|8|in|mm|ar=on}}
|-
!{{rh2}} title="5R or 2L photo print"| {{resx|5|7}}<!--PWG 5101.1-->
| {{size|5|7|in|mm|ar=on}}
|}

The United States, Canada, and the Philippines<ref name="CLDR">Belize, Canada, Chile, Colombia, Costa Rica, El Salvador, Guatemala, Mexico, Nicaragua, Panama, Philippines, Puerto Rico, United States, Venezuela according to {{cite web |title=Territory Information |work=CLDR |version=31 |url=https://www.unicode.org/cldr/charts/latest/supplemental/territory_information.html |access-date=24 March 2018 |archive-url=https://web.archive.org/web/20180620043901/http://www.unicode.org/cldr/charts/latest/supplemental/territory_information.html |archive-date=20 June 2018 |url-status=live}}, which is a data collection used by almost all software manufacturers.</ref> primarily use a different system of paper sizes from the rest of the world. The current standard sizes are unique to those countries, although due to the size of the North American market and proliferation of both software and printing hardware from the region, other parts of the world have become increasingly familiar with these sizes (though not necessarily the paper itself). Some traditional North American inch-based sizes differ from the [[#Traditional inch-based paper sizes|Imperial British sizes]] described below.

==== Common American loose sizes ====

{{anchor|Letter}}{{anchor|Legal}}{{anchor|Ledger}}{{anchor|Tabloid}}{{anchor|American Quarto}}
''Letter, Legal'' and ''Ledger/Tabloid'' are by far the most commonly used of these for everyday activities, and the only ones included in [[Cascading Style Sheets]] (CSS).

The origins of the exact dimensions of Letter size paper are lost in tradition and not well documented. The American Forest and Paper Association argues that the dimension originates from the days of manual papermaking and that the 11-inch length of the page is about a quarter of "the average maximum stretch of an experienced vatman's arms."<ref name="US">{{cite web |url=http://www.afandpa.org/paper.aspx?id=511 |title=Why is the standard paper size in the U.S. 8 1/2" x 11"? |access-date=4 August 2009 |publisher=American Forest and Paper Association |url-status=dead |archive-url=https://web.archive.org/web/20120220192919/http://www.afandpa.org/paper.aspx?id=511 |archive-date=20 February 2012}}</ref> However, this does not explain the width or aspect ratio.

Outside of North America, Letter size may also be known as "American Quarto".<ref>{{cite web |url=http://www.dimensionsguide.com/junior-legal-paper-size/ |title=Junior Legal Paper Size |publisher=Dimensions Guide |access-date=21 February 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100704081857/http://www.dimensionsguide.com/junior-legal-paper-size/ |archive-date=4 July 2010}}</ref> If one accepts some trimming, the size is indeed one quarter of the old Imperial paper size known as Demy, {{convert|17+1/2|×|22+1/2|inch|mm|0|abbr=on}}.<ref>{{cite book |author-last=Fyffe |author-first=Charles |title=Basic Copyfitting |publisher=Studio Vista |date=1969 |location=London |isbn=978-0-289-79705-1 |page=74}}</ref> 
Manufacturers of computer printers, however, recognize inch-based ''Quarto'' as {{frac|10|5|6}} or {{cvt|10.83|inch|mm}} long.<ref name="PWG"/>

==== Usage and adoption ====

US paper sizes are currently standard in the United States and are the most commonly used formats at least in the Philippines, most of [[Mesoamerica]]<ref>{{cite web |url=http://www.armada.mil.co/index.php?idcategoria=251610&download=Y |title=Armada mil |access-date=12 December 2010 |archive-url=https://web.archive.org/web/20110524053225/http://www.armada.mil.co/index.php?idcategoria=251610&download=Y |archive-date=24 May 2011 |url-status=live}}</ref> and Chile. The latter use US Letter, but their Legal size is 13 inches tall (recognized as ''Foolscap'' by printer manufacturers,<ref name="PWG"/> i.e. one inch shorter than its US equivalent.<ref>{{cite web |url=https://bz.apache.org/ooo/show_bug.cgi?id=91260 |title=Request for inclusion of Page Size 8.5"×13" |access-date=11 August 2008 |author-first=Rally |author-last=de Leon}}</ref>

{{anchor|Carta}}{{anchor|Oficio}}
Mexico and Colombia, for instance, have adopted the ISO standard, but the US Letter format is still the system in use throughout the country. It is rare to encounter ISO standard papers in day-to-day uses, with ''Carta'' (Letter), ''Oficio'' (Government-Legal), and ''Doble carta'' (Ledger/Tabloid) being nearly universal. 
Printer manufacturers, however, recognize ''Oficio'' as {{cvt|13.4|inch|mm}} long.<ref name="PWG"/>

In Canada, select US paper sizes are a ''de facto'' standard.

==== Variant American loose sizes ====

{{anchor|Government Letter}}{{anchor|}}
There is an additional paper size, {{cvt|8|×|10+1/2|inch|abbr=|round=5}}, to which the name ''Government-Letter'' was given by the [[IEEE]] [[Printer Working Group]] (PWG).<ref name="PWG"/> It was prescribed by [[Herbert Hoover]] when he was [[Secretary of Commerce]] to be used for US government forms, apparently to enable discounts from the purchase of paper for schools, but more likely due to the standard use of trimming books (after binding) and paper from the standard letter size paper to produce consistency and allow "bleed" printing. In later years, as photocopy machines proliferated, citizens wanted to make photocopies of the forms, but the machines did not generally have this size of paper in their bins. [[Ronald Reagan]] therefore had the US government switch to regular Letter size, which is half an inch both longer and wider.<ref name="US"/> The former government size is still commonly used in spiral-bound [[notebook]]s, for children's writing and the like, a result of trimming from the current Letter dimensions.

{{anchor|Statement}}{{anchor|Stationery}}{{anchor|Memo}}{{anchor|Half-Letter}}{{anchor|Half-A}}
By extension of the American standards, the halved Letter size, {{cvt|5+1/2|×|8+1/2|inch|abbr=|round=5}}, meets the needs of many applications. It is variably known as ''Statement'', ''Stationery'', ''Memo'', ''Half Letter'', ''Half A'' (from ANSI sizes) or simply ''Half Size'', and as ''Invoice'' by printer manufacturers.<ref name="PWG"/> Like the similar-sized ISO A5, it is used for everything from personal letter writing to official aeronautical maps. Organizers, notepads, and diaries also often use this size of paper; thus 3-ring [[binders]] are also available in this size. Booklets of this size are created using word processing tools with landscape printing in two columns on letter paper which are then cut or folded into the final size.

A foot-long sheet with the common width of Letter and (Government) Legal, i.e. {{cvt|8+1/2|x|12|inch|abbr=|round=5}}, would have an aspect ratio very close to the square root of two as used by international paper sizes and would actually almost exactly match [[ISO 217|ISO RA4]] (215&nbsp;mm × 305&nbsp;mm). This size is sometimes known as ''European Fanfold''.<ref name="PWG"/>

{{anchor|Executive}}
While ''Executive'' refers to {{cvt|7+1/4|×|10+1/2|inch|abbr=|round=5}} in America, the Japanese organization for standardization specified it  as {{cvt|216|×|330|mm|abbr=}}, which is elsewhere known as Government Legal or Foolscap.

{{anchor|ANSI paper sizes}}{{anchor|ANSI}}

==== Standardized American paper sizes ====
[[File:ANSI size illustration2.svg|thumb|right|A size chart illustrating the ANSI sizes, superimposed on an "ANSI E" sheet]]

In 1996<!-- https://sizes.com/materials/paperUStech.htm claims that it was withdrawn in 1995!-->, the [[American National Standards Institute]] adopted [[ANSI/ASME Y14.1]] which defined a regular series of paper sizes based upon the ''de facto'' standard {{cvt|8+1/2|×|11|inch|mm|sigfig=3}} Letter size which it assigned "ANSI A", intended for technical drawings, hence sometimes labeled "Engineering". This series is somewhat similar to the ISO standard in that cutting a sheet in half would produce two sheets of the next smaller size and therefore also includes Ledger/Tabloid<ref name="PPD">{{cite web  |author=Adobe Systems Incorporated |author-link=Adobe Systems |date=9 February 1996 |title=PostScript Printer Description File Format Specification |edition=4.3 |location=[[San Jose, California]] |page=191 |url=http://partners.adobe.com/public/developer/en/ps/5003.PPD_Spec_v4.3.pdf |access-date=6 March 2008 |url-status=dead |archive-url=https://web.archive.org/web/20080723180944/http://partners.adobe.com/public/developer/en/ps/5003.PPD_Spec_v4.3.pdf |archive-date=23 July 2008}}{{better source|date=July 2016}}</ref> as "ANSI B". Unlike the ISO standard, however, the arbitrary base sides forces this series to have two alternating aspect ratios. For example, ANSI A is less elongated than A4, while ANSI B is more elongated than A3.

The Canadian standard CAN2 9.60-M76 and its successor CAN/CGSB 9.60-94 "Paper Sizes for Correspondence" specified paper sizes P1 through P6, which are the U.S. paper sizes rounded to the nearest 5&nbsp;mm.<ref>{{cite web |url=http://www.cl.cam.ac.uk/~mgk25/iso-paper.html |title=International standard paper sizes |access-date=6 March 2008 |author-last=Kuhn |author-first=Markus |archive-url=https://web.archive.org/web/20080115144056/http://www.cl.cam.ac.uk/~mgk25/iso-paper.html |archive-date=15 January 2008 |url-status=live}}</ref> All custom Canadian paper size standards were withdrawn in 2012.<ref name="CAN">
{| class="wikitable"
|+ Canadian custom paper size standards 
! Number !! Title !! Original CAN2 release !! CAN/CGSB replacement !! Withdrawal
|-
| 9.60 || Paper Sizes for Correspondence || [http://www.scc.ca/en/standardsdb/standards/2700 1976-04] || [http://www.scc.ca/en/standardsdb/standards/5790 1994-07] ||rowspan=4| 2012-04
|-
| 9.61 || Paper Sizes for Printing || [http://www.scc.ca/en/standardsdb/standards/2701 1976-04] || [http://www.scc.ca/en/standardsdb/standards/5789 1994-07]
|-
| 9.62 || Paper Sizes for Single Part Continuous Business Forms || [http://www.scc.ca/en/standardsdb/standards/2417 1981-12] || [http://www.scc.ca/en/standardsdb/standards/5788 1994-07]
|-
| 9.64 || Drawing Sheet Sizes || [http://www.scc.ca/en/standardsdb/standards/2512 1979-04] || [http://www.scc.ca/en/standardsdb/standards/5786 1994-07]
|-
| 200.2 || Common Image Area for Paper Sizes P4 and A4 || [http://www.scc.ca/en/standardsdb/standards/2464 1979-04] || || 2012-03
|}
</ref>

With care, documents can be prepared so that the text and images fit on either ANSI or their equivalent ISO sheets at a 1:1 reproduction scale.

{| class="wikitable"
|+ ANSI and CAN paper sizes
|-
! US size
! inch × inch !! mm × mm !!title="aspect ratio"| AR !!colspan=2| Canadian size (mm × mm) !!colspan=2| Similar size (mm × mm)
|-
| colspan=4 {{n/a}} || CAN P6 || 107 × 140 || ISO A6 || 105 × 148
|- title="Memo, Statement"
| colspan=4 {{n/a}} || CAN P5 || 140 × 215 || ISO A5 || 148 × 210
|- title="Letter"
! ANSI A
|  {{frac|8|1|2}} × 11 || 216 × 279 || 17:22 || CAN P4 || 215 × 280 || ISO A4 || 210 × 297
|- title="Ledger, Tabloid"
! ANSI B
| 11 × 17 || 279 × 432 || 11:17 || CAN P3 || 280 × 430 || ISO A3 || 297 × 420
|-
! ANSI C
| 17 × 22 || 432 × 559 || 17:22 || CAN P2 || 430 × 560 || ISO A2 || 420 × 594
|-
! ANSI D
| 22 × 34 || 559 × 864 || 11:17 || CAN P1 || 560 × 860 || ISO A1 || 594 × 841
|-
! ANSI E
| 34 × 44 || 864 × 1118 || 17:22 || colspan=2 {{n/a}} || ISO A0 || 841 × 1187
|}

Other, informal, larger sizes continuing the alphabetic series illustrated above exist, but they are not part of the series ''per se'', because they do not exhibit the same aspect ratios. For example, Engineering F size is {{cvt|28|×|40|inch|mm|0|disp=or}} with ca. 1.4286:1; it is commonly required for [[Naval Facilities Engineering Command|NAVFAC]] drawings, but is generally less commonly used. Engineering G size is {{cvt|22+1/2|inch|mm|0}} high, but it is a roll format with a variable width up to {{cvt|90|inch|m}} in increments of {{cvt|8+1/2|inch|mm|0}}. Engineering H through N sizes are also roll formats.

Such huge sheets were at one time used for full-scale layouts of aircraft parts, automotive parts, wiring harnesses, and the like, but are slowly being phased out, due to widespread use of [[computer-aided design]] (CAD) and [[computer-aided manufacturing]] (CAM). Some visual arts fields also continue to use these paper formats for large-scale printouts, such as for displaying digitally painted character renderings at life-size as references for makeup artists and costume designers or to provide an immersive landscape reference.

==== Architectural sizes ====

[[File:ARCH PAPER SIZES v3.svg|thumb|right|A size chart illustrating the Architectural sizes]]
In addition to the system as listed above, there is a corresponding series of paper sizes used for [[architecture|architectural]] purposes defined in the same standard, ANSI/ASME Y14.1, which is usually abbreviated "Arch". This series also shares the property that bisecting each size produces two of the size below, with alternating aspect ratios. It may be preferred by North American architects because the aspect ratios (4:3 and 3:2) are ratios of small integers, unlike their ANSI (or ISO) counterparts. Furthermore, the aspect ratio 4:3 matches the traditional aspect ratio for computer displays.

The size Arch E1 has a different aspect ratio because it derives from adding 6 inches to each side of Arch D or subtracting the same amount from Arch E. Printer manufacturer recognize it as ''wide-format''.<ref name="PWG"/> An intermediate size between Arch C and D with a long side of {{convert|30|inch|mm}} does not exist.
<!-- Someone please explain the weird E2 and E3 here! PWG 5101.1 now has them -->

{| class="wikitable"
|+ US architectural standard paper sizes<ref>{{cite web |url=https://sizes.com/materials/paperUStech.htm |title=Technical drawing paper sizes in the United States |archive-url=https://web.archive.org/web/20161008145734/http://sizes.com/materials/paperUStech.htm |archive-date=8 October 2016}} at sizes.com</ref>
|-
!colspan=2| Names
! inch × inch !! mm × mm !!title="aspect ratio"| AR
|-
! Arch A !! Arch 1
| {{size|9|12|in|mm|ar=on}}
|-
! Arch B !! Arch 2
| {{size|12|18|in|mm|ar=on}}
|-
! Arch C !! Arch 3
| {{size|18|24|in|mm|ar=on}}
|-
! Arch D !! Arch 4
| {{size|24|36|in|mm|ar=on}}
|- title="wide format"|
! Arch E1 !! Arch 5
| {{size|30|42|in|mm|ar=on}}
|-
!colspan=2| Arch E2<ref name="PWG"/>
| {{size|26|38|in|mm|ar=on}}
|-
!colspan=2| Arch E3<ref name="PWG"/>
| {{size|27|39|in|mm|ar=on}}
|-
! Arch E !! Arch 6
| {{size|36|48|in|mm|ar=on}}
|}

=== Demitab <span class="anchor" id="demitab"></span><span class="anchor" id="demi-tab"></span>===

The '''demitab''' or '''demi-tab''' (a [[portmanteau]] of the French word '{{lang|fr|demi}}' [half] and 'tabloid') is {{convert|8|x|10+1/2|inch|mm|0|abbr=on}}, i.e.  roughly one half of a sheet of {{convert |11|x|17|inch|mm|0|abbr=on}} tabloid-size paper.<ref>{{Cite web |url=http://horizonpublications.ca/html/max_image_area.php |publisher=Horizon Publications |title=Maximum Image Area for printing at Horizon Publications |access-date=28 August 2009 |archive-url=https://web.archive.org/web/20081009210153/http://www.horizonpublications.ca/html/max_image_area.php |archive-date=9 October 2008 |url-status=dead }}</ref>

"Demitab", "[[broadsheet]]" or [[tabloid (newspaper format)|"tabloid" format newspapers]] are not necessarily printed on paper measuring exactly their [[Real versus nominal value|nominal size]].

=== Notebook sizes ===

The sizes listed above are for paper sold loose in [[paper ream|ream]]s. There are many sizes of [[notebook|tablets of paper]], that is, sheets of paper bound at one edge, usually by a strip of plastic or hardened [[polyvinyl acetate|PVA adhesive]]. Often there is a pad of [[paperboard|cardboard]] (also known as paperboard or greyboard) at the bottom of the stack. Such a tablet serves as a portable writing surface, and the sheets often have lines printed on them, usually in [[Non-photo blue|non-repro blue]], to make writing in a line easier. An older means of binding is to have the sheets stapled to the cardboard along the top of the tablet; there is a line of perforated holes across every page just below the top edge from which any page may be torn off. Lastly, a pad of sheets each weakly stuck with adhesive to the sheet below, trademarked as "[[Post-It]]" or "Stick-Em" and available in various sizes, serve as a sort of tablet.

"Letter pads" are {{cvt|8+1/2|x|11|inch|mm}}, while the term "legal pad" is often used by laymen to refer to pads of various sizes including those of {{cvt|8+1/2|x|14|inch|mm}}. [[stenography|Stenographers]] use "steno pads" of {{cvt|6|x|9|inch|mm}}. The steno pad size is also used by [[Scholastic Corporation]] as the textblock size of their hardcover editions of the ''[[Harry Potter]]'' novels, with paperback editions using DIN D6.

=== Envelope sizes ===

{| class="wikitable"
|+ US envelopes<ref name="PWG"/>
! Name !! inch × inch !! mm × mm !!title="aspect ratio"| AR
|-
! Personal
| {{size|3+5/8|6+1/2|in|mm|ar=on}}
|-
! Monarch
| {{size|3+7/8|7+1/2|in|mm|ar=on}}
|-
! A2
| {{size|4+3/8|5+3/4|in|mm|ar=on}}
|-
! #9
| {{size|3+7/8|8+7/8|in|mm|ar=on}}
|-
! #10, Commercial
| {{size|4+1/8|9+1/2|in|mm|ar=on}}
|-
! #11
| {{size|4+1/2|10+3/8|in|mm|ar=on}}
|-
! #12
| {{size|4+3/4|11|in|mm|ar=on}}
|-
! #14
| {{size|5|11+1/2|in|mm|ar=on}}
|}
<!--PWF5101.1: 6x9, 7x9, 9x11, 9x12, 10x13, 10x14, 10x15-->

{| class="wikitable"
|+ US Postal Service size limitations, height × width × thickness<ref>{{cite book |publisher=United States Postal Service |url=http://pe.usps.com/text/dmm300/101.htm#6_3_1 |title=DMM 101: Physical Standards |archive-url=https://web.archive.org/web/20140426235609/http://pe.usps.com/text/dmm300/101.htm#6_3_1 |archive-date=26 April 2014 |chapter=Section 6.3.2: Postcard Dimensions |access-date=26 April 2014}}</ref>
! Mail piece
! inch × inch × inch !! mm × mm × mm
|-
!title="The minimal thickness is just 0.007-inch if the shorter side does not exceed 4.25 inches and the longer side does not exceed 6 inches."| Minimum 
| {{convert|3+1/2|x|5|x|0.009|in|mm|disp=tablecen|sigfig=3}} 
|-
! Postcard maximum 
| {{convert|4+1/4|x|6|x|0.016|in|mm|disp=tablecen|sigfig=3}}
|-
! Letter maximum 
| {{convert|6+1/8|x|11+1/2|x|1/4|in|mm|disp=tablecen|sigfig=3}}
|-
! Flat-size maximum
| {{convert|12|x|15|x|3/4|in|mm|disp=tablecen|sigfig=3}}
|}

This implies that all postcards have an aspect ratio in the range from {{resratio|20|17}} = 1.18 to {{resratio|12|7}} = 1.71, but the machinable aspect ratio is further restricted to a minimum of 1.30.
The only ISO 216 size in the US postcard range is A6.
The theoretical maximum aspect ratio for enveloped letters is {{resratio|23|7}} = 3.29, but is explicitly limited to 2.50.

=== Personal organizer sizes ===
{| class="wikitable"
|+ US [[personal organizer]]s
! Company!!Name!! inch × inch || mm × mm || Holes
|-
!rowspan=7| [[Filofax]]<ref>{{cite web |url=http://www.filofax.sg/sizeguide/ |title=Filofax |url-status=dead |archive-url=https://web.archive.org/web/20100927152900/http://www.filofax.sg/sizeguide/ |archive-date=27 September 2010}}</ref>
! M2
| {{size|2+1/2|4|in|mm}} || 3 holes
|-
! Mini
| {{size|2+5/8|4+1/8|in|mm}} || 5 holes
|-
! Pocket
| {{size|3+1/6|4+3/4|in|mm}} || 6 holes
|-
! Personal, Slimline
| {{size|3+3/4|6+3/4|in|mm}} || 6 holes
|-
! A5
|({{frac|5|13|16}} × {{frac|8|9|32}}) || 148 × 210 || 6 holes
|-
! Deskfax (B5)
| ({{frac|6|15|16}} × {{frac|9|27|32}})
| 176 × 250 || 9 holes
|-
! A4
| ({{frac|8|9|32}} × {{frac|11|11|16}})
| 210 × 297 || 4 holes
|-
!rowspan=5| [[Franklin Planner]]<ref>{{cite web |url=http://www.franklinplanner.com |title=Franklin Planner |access-date=28 April 2019 |archive-url=https://web.archive.org/web/20180801231712/http://www.franklinplanner.com/ |archive-date=1 August 2018 |url-status=live}}</ref>
! Micro ({{frac|1|8}}-Letter)
| {{size|2+5/8|4+1/4|in|mm}} ||
|-
! Pocket
| {{size|3+1/2|6|in|mm}} ||
|-
! Compact
| {{size|4+1/4|6+3/4|in|mm}} ||
|-
! Classic ({{frac|1|2}}-Letter)
| {{size|5+1/2|8+1/2|in|mm}} ||
|-
! Monarch (Letter)
| {{size|8+1/2|11|in|mm}} ||
|-
! [[Jeppesen]]
! Aeronautical Chart ({{frac|1|2}}-Letter)
| {{size|5+1/2|8+1/2|in|mm}} || 7 holes; [[FAA]]: 3 holes at top
|}

=== Index card sizes ===
{{main|index card}}

{| class="wikitable"
|+ US index cards
! inch × inch  !! mm × mm !!title="aspect ratio"| AR
|-
| {{size|3|5|in|mm|ar=on}}
|-
| {{size|4|6|in|mm|ar=on}}
|-
| {{size|5|8|in|mm|ar=on}}
|-
| {{size|6|8|in|mm|ar=on}}
|}

=== Photography sizes ===
{{main|Photo print sizes}}
{{cleanup|table|reason=Names need explanation, i.e. expansion of acronyms.|date=November 2015}}

{| class="wikitable"
|+ US [[photographic paper]] sizes
! Name
! inch × inch  !! mm × mm !!title="aspect ratio"| AR
|-
! 2R
| {{size|2+1/2|3+1/2|in|mm|ar=on}}
|-
! -
| {{size|3|5|in|mm|ar=on}}
|-
! LD, DSC
| {{size|3+1/2|4+2/3|in|mm|ar=on}}
|-
! 3R, L
| {{size|3+1/2|5|in|mm|ar=on}}
|-
! LW
| {{size|3+1/2|5+1/4|in|mm|ar=on}}
|-
! KGD
| {{size|4|5+1/3|in|mm|ar=on}}
|-
! 4R, KG
| {{size|4|6|in|mm|ar=on}}
|-
! 2LD, DSCW
| {{size|5|6+2/3|in|mm|ar=on}}
|-
! 5R, 2L
| {{size|5|7|in|mm|ar=on}}
|-
! 2LW
| {{size|5|7+1/2|in|mm|ar=on}}
|-
! 6R
| {{size|6|8|in|mm|ar=on}}
|-
! 8R, 6P
| {{size|8|10|in|mm|ar=on}}
|-
! S8R, 6PW
| {{size|8|12|in|mm|ar=on}}
|-
! 11R
| {{size|11|14|in|mm|ar=on}}
|-
! A3+, Super B
| {{size|13|19|in|mm|ar=on}}
|}

=== Grain ===

Most industry standards express the direction of the [[Paper#Paper grain|grain]] last when giving dimensions (that is, 17&nbsp;×&nbsp;11 inches is short grain paper and 11&nbsp;×&nbsp;17 inches is long grain paper), although alternatively the grain alignment can be explicitly indicated with an underline (<u>11</u>&nbsp;×&nbsp;17 is a short grain) or the letter "M" for "machine" (11M&nbsp;×&nbsp;17 is a short grain). Grain is important because the paper will crack if folded across the grain: for example, if a sheet 17&nbsp;×&nbsp;11 inches is to be folded to divide the sheet into two 8.5&nbsp;×&nbsp;11 halves, then the grain will be along the 11-inch side.<ref name="xerox-grain">{{cite web |url=http://www.xerox.com/printer-supplies/paper-stock/paper-grain/enus.html |title=Paper Grain & Smoothness: Don't Go Against the Grain |publisher=[[Xerox]] Corp. |quote=A paper mill may indicate paper grain on carton and ream labels, product brochures, swatch books and price lists in several ways:<br/>1. You may see the words Grain Long or Grain Short.<br/>2. The dimension parallel to the grain may be underscored. For example, 8.5x<u>11</u> indicates long grain, while <u>11</u>×17 indicates short grain.<br/>3. 'M' may be used to indicate machine direction, for example, 11M×17 indicates short grain.<br/>Fold paper parallel to the grain direction. Paper folded against the grain may be rough and crack along the folded edge. The heavier the paper, the more likely roughness and cracking will occur. |access-date=10 May 2013 |archive-url=https://web.archive.org/web/20130425030450/http://www.xerox.com/printer-supplies/paper-stock/paper-grain/enus.html |archive-date=25 April 2013 |url-status=dead }}</ref> Paper intended to be fed into a machine that will bend the paper around rollers, such as a [[printing press]], [[photocopier]] or [[typewriter]], should be fed grain edge first so that the axis of the rollers is along the grain.
<!-- This explains the difference between Ledger and Tabloid. -->

{{Anchor|Foolscap}}

=== Traditional inch-based paper sizes ===
[[File:Paper size - US system.svg|thumb|upright=1.5|Traditional and standardized paper formats still relevant in the US]]

Traditionally, a number of different sizes were defined for large sheets of paper, and paper sizes were defined by the sheet name and the number of times it had been folded. Thus a full sheet of "royal" paper was 25 × 20 inches, and "royal octavo" was this size folded three times, so as to make eight sheets, and was thus 10 × {{frac|6|1|4}} inches. Royal sizes were used for posters and billboards.

{| class="wikitable"
|+ Common divisions and their abbreviations
|-
! Name
! Abbr. !! Folds !! Leaves !! Pages
|-
! [[Folio (printing)|Folio]]<!-- , Folacio -->
| fo, f || 1 || 2 || 4
|-
! Quarto
|  4to || 2 || 4 || 8
|-
! Sexto, sixmo
|  6to, 6mo || 3 || 6 || 12
|-
! Octavo<!-- , Belagionastic -->
|  8vo || 3 || 8 || 16
|-
! Duodecimo, twelvemo
| 12mo || 4 || 12 || 24
|-
! Sextodecimo, sixteenmo
| 16mo || 4 || 16 || 32
|}

{{cleanup|table|reason=Badly sourced collection of sizes, correct values may vary, variation through trimming is ignored and some designations are confusing, in short: it is probably full of mistakes.|date=January 2020}}
Imperial sizes were used in the United Kingdom and its territories and some survived in US book printing.

{| class="wikitable"
|+ Imperial paper sizes
|-
! Name !! Variant
! inch × inch !! mm × mm !!title="aspect ratio"| AR
|-
! Emperor
| UK || {{size|48|72|in|mm}} || 1.5
|-
! Quad Royal
| US || {{size|40|50|in|mm}} || 1.25
|-
! Quad Demy
| US || {{size|35|45|in|mm}} || 1.2857
|-
! Antiquarian
| UK || {{size|31|53|in|mm}} || 1.7097
|-
! Grand Eagle
| UK || {{size|28+3/4|42|in|mm}} || 1.4609
|-
! Double Elephant
| UK || {{size|26+3/4|40|in|mm}} || 1.4984
|-
! Atlas
| UK || {{size|26|34|in|mm}} || 1.3077
|-
! Double Royal
| US || {{size|25|40|in|mm}}  || 1.6
|-
! Colombier
| UK || {{size|23+1/2|34+1/2|in|mm}} || 1.4681
|-
!rowspan=2| Double Demy
| UK || {{size|22+1/2|35+1/2|in|mm}} || 1.5{{overline|7}}
|-
| US || {{size|22+1/2|35|in|mm}} || 1.{{overline|5}}
|-
! Imperial
| UK || {{size|22|30|in|mm}} || 1.3636 <!-- 9 × 7 -->
|-
! Double Large Post
| UK || {{size|21|33|in|mm}} || 1.5713
|-
! {{visible anchor|Elephant}}
| both || {{size|23|28|in|mm}} || 1.2174
|-
! Princess
| UK || {{size|22+1/2|28|in|mm}} || 1.3023
|-
! Cartridge
| UK || {{size|21|26|in|mm}} || 1.2381
|-
! Royal
| both || {{size|20|25|in|mm}} || 1.25
|-
! Sheet, Half Post<!--this seems incorrect!-->
| UK || {{size|19+1/2|23+1/2|in|mm}} || 1.2051
|-
! Double Post
| UK || {{size|19|30+1/2|in|mm}} || 1.6052
|-
! Super Royal
| UK || {{size|19|27|in|mm}} || 1.4203
|-
! Broadsheet
| US || {{size|18|24|in|mm}} || 1.{{overline|3}}
|-
!rowspan=2| Medium
| UK || {{size|17+1/2|23|in|mm}} || 1.2425
|-
| US || {{size|18|23|in|mm}} || 1.2{{overline|7}}
|-
! Demy<span class="anchor" id="Demy"></span><!--Please leave. Text in another article links here.-->
| both || {{size|17+1/2|22+1/2|in|mm}} || 1.2857
|-
! Copy Draught
| UK || {{size|16|20|in|mm}} || 1.25
|-
!rowspan=2| Large Post
| UK || {{size|15+1/2|20|in|mm}} || 1.2903
|-
| US || {{size|16+1/2|21|in|mm}} || 1.{{overline|27}}
|-
!rowspan=2|Post
| UK || {{size|15+1/2|19+1/4|in|mm}} || 1.2419
|-
| US || {{size|15+1/2|19+1/2|in|mm}} || 1.2581
|-
! Crown
| both || {{size|15|20|in|mm}} || 1.{{overline|3}}
|-
! Pinched Post
| UK || {{size|14+3/4|18+1/2|in|mm}} || 1.2533
|-
!rowspan=2| Foolscap
| UK || {{size|13|16|in|mm}} || 1.2303
|-
| US || {{size|13+1/2|17|in|mm}} || 1.2595
|-
!rowspan=2| [[Foolscap Folio]]
| UK || {{size|13|8|in|mm}} || 1.6256
|-
| US || {{size|13+1/2|8+1/2|in|mm}} || 1.5880
|-
! Small Foolscap
| UK || {{size|13+1/4|16+1/2|in|mm}} || 1.2453
|-
! Brief
| UK || {{size|13+1/2|16|in|mm}} || 1.1852
|-
! Pott
| UK || {{size|12+1/2|15|in|mm}} || 1.2
|-
! Quarto
| <!-- 8 × 10 --> US || {{size|9|11|in|mm}} || 1.{{overline|2}}
|-
! Executive, Monarch
| US || {{size|7+1/4|10+1/2|in|mm}} || 1.4483
|}

== Traditional British paper sizes ==
{{hatnote|The sizes used for historic "folio" books use a [[Folio#Size|different system]].}}
Traditional British paper sizes are referred to by the number of sheets that can be cut from a sheet of uncut paper.<ref name="old-imperial">{{cite web |title=British Imperial Paper Sizes |url=https://www.papersizes.org/old-imperial-sizes.htm |website=PaperSizes.org |access-date=8 August 2022}}</ref> The standard Imperial uncut paper sizes used in offices and schools were "foolscap", "post", and "copy". Each uncut sheet can then be halved into [[Folio|folios]], quartered into [[Quarto|quartos]], or eighthed into [[Octavo|octavos]]. 

{| class="wikitable"
|+ British Imperial paper sizes<ref name="old-imperial"/>
|-
! Name
! inch × inch !! mm × mm !!title="aspect ratio"| AR
|-
! Foolscap
| {{size|13.25|16.5|in|mm|ar=on}}
|-
! Foolscap Folio (Folio)
| {{size|8|13|in|mm|ar=on}}
|-
! Foolscap Quarto (Kings)
| {{size|6.5|8|in|mm|ar=on}}
|-
! Foolscap Octavo
| {{size|4|6.5|in|mm|ar=on}}
|-
! Post
| {{size|15|19|in|mm|ar=on}}
|-
! Post Folio
| {{size|9.5|15|in|mm|ar=on}}
|-
! Post Quarto (Imperial)
| {{size|7|9|in|mm|ar=on}}
|-
! Post Octavo
| {{size|4.5|7|in|mm|ar=on}}
|-
! Copy
| {{size|16|20|in|mm|ar=on}}
|-
! Copy Folio
| {{size|10|16|in|mm|ar=on}}
|-
! Copy Quarto (Quarto)
| {{size|8|10|in|mm|ar=on}}
|-
! Copy Octavo
| {{size|5|8|in|mm|ar=on}}
|-
|}

== Traditional French paper sizes ==

Before the adoption of the ISO standard system in 1967, France had its own paper size system. Raisin format is still in use today for artistic paper. All are standardized by the [[Association française de normalisation|AFNOR]].<ref>{{cite book |title=Norme NF Q 02-000: Dimensions des papiers d'écriture et de certaines catégories de papiers d'impression |publisher=[[Association française de normalisation]] |language=fr}}</ref> Their names come from the [[watermark]]s that the papers were branded with when they were handcrafted, which is still the case for certain art papers. They also generally exist in double versions where the smallest measure is multiplied by two, or in quadruple versions where both measures have been doubled.

{| class="wikitable"
|+ AFNOR paper sizes
! Name !! Format (cm × cm) !! Use
|-
! Cloche
| 30 × 40
|
|-----
! Pot, écolier
| 31 × 40
|
|-
! Tellière
| 34 × 44
| old French administration
|-----
! Couronne écriture
| 36 × 46
|
|-
! Couronne édition
| 37 × 47
|
|-
! Roberto
| 39 × 50
| anatomic drawing
|-
! Écu
| 40 × 52
|
|-
! Coquille
| 44 × 56
|
|-----
! Carré
| 45 × 56
|
|-
! Cavalier
| 46 × 62
|
|-----
! Demi-raisin
| 32,5 × 50
| drawing
|-
! Raisin
| 50 × 65
| drawing
|-
! Double raisin
| 65 × 100
|
|-----
! Jésus
| 56 × 76
| [[Atlas des chemins vicinaux|Atlas des sentiers et chemins vicinaux]]
|-----
! Soleil
| 60 × 80
|
|-
! Colombier affiche
| 60 × 80
|
|-
! Colombier commercial
| 63 × 90
|
|-----
! Petit Aigle
| 70 × 94
|
|-
!rowspan=3| Grand Aigle
| 75 × 105
|rowspan=3| [[Plan cadastral primitif|Plans cadastraux primitifs]] <br/> (Napoleonic land registry)
|-
| 75 × 106<ref>{{cite web |url=http://www.cnrtl.fr/lexicographie/aigle |title=AIGLE: Définition de AIGLE |publisher=[[Centre national de ressources textuelles et lexicales]] (CNRTL) |access-date=22 May 2015 |language=fr |archive-url=https://web.archive.org/web/20150522112240/http://www.cnrtl.fr/lexicographie/aigle |archive-date=22 May 2015 |url-status=live}}</ref>
|-
| 75 × 110<ref>{{cite web |url=http://www.clairefontaine.com/Dossiers/Beaux-Arts/Plus-d-infos-sur-le-papier-Beaux-Arts/Les-formats.html |archive-url=https://web.archive.org/web/20060319010826/http://www.clairefontaine.com/Dossiers/Beaux-Arts/Plus-d-infos-sur-le-papier-Beaux-Arts/Les-formats.html |url-status=dead |archive-date=19 March 2006 |title=L'origine des noms de papier |language=fr}}</ref>
|-----
! Grand Monde
| 90 × 126
|
|-----
! Univers
| 100 × 130
|
|}

== Business card sizes ==
{{main|Business card#Dimensions}}

{| class="wikitable sortable"
|+ Common business card sizes
! Origin
! mm × mm !! inch × inch  !!title="aspect ratio"| AR
|-
! A8
| 74 × 52 || {{frac|2|15|16}} × {{frac|2|1|16}} || {{sort|1.423|√2}}
|- title="envelope?"
! B8
| 88 × 62 || {{frac|3|4|9}} × {{frac|2|4|9}} || {{sort|1.419|√2}}
|- style="display:none"
! C8
| 81 × 57 || {{frac|3|3|16}} × {{frac|2|1|4}} || {{sort|1.421|√2}}
|- style="display:none"
! Iranian
| 85 × 48 || {{frac|3|1|3}} × {{frac|1|8|9}} || 1.771
|-
! Western Europe
| 85 × 55 || {{frac|3|1|3}} × {{frac|2|1|6}} || {{ratio|17|11}}
|-
! International
| 86 × 54 <!-- ISO/IEC 7810 ID-1 is exactly 53.98 mm × 85.6 mm, but business cards only approximate this size -->|| {{frac|3|3|8}} × {{frac|2|1|8}} || {{ratio|27|17}}
|-
! North America
| 89 × 51 || {{frac|3|1|2}} × 2<!--only inch-based size--> || {{ratio|7|4}}
|-
! Eastern Europe, Asia, Africa, South America
| 90 × 50 || {{frac|3|9|16}} × 2 || {{ratio|9|5}}
|-
! East Asia
| 90 × 54 || {{frac|3|9|16}} × {{frac|2|1|8}} || {{ratio|5|3}}
|-
! Scandinavia, Southeast Asia, Oceania
| 90 × 55 || {{frac|3|9|16}} × {{frac|2|1|6}} || {{ratio|18|11}}
|-
! Japan
| 91 × 55 || {{frac|3|7|12}} × {{frac|2|1|6}} || 1.6{{overline|54}}
|}

The international business card has the size of the smallest rectangle containing a credit card rounded to full millimeters, but in Western Europe, it is rounded to half centimetres (rounded up in Northern Europe), in Eastern Europe to full centimetres, in North America to half inches. However, ''credit card size'', as defined in [[ISO/IEC 7810]], also specifies rounded corners and thickness.

== Newspaper sizes ==
{{Main|Newspaper format}}

{{comparison newspaper size.svg}}

Newspapers have a separate set of sizes.

* [[Compact (newspaper)|Compact]]: AR 1.54
* [[Berliner (format)|Berliner]]: aspect ratio is 1.5
* [[Rhenish (format)|Rhenish]]: AR 1.4–1.5
* [[Tabloid (newspaper format)|Tabloid]] 1.34
* [[Broadsheet]]: aspect ratio 1.25

In a recent trend<ref>{{cite web |url=http://www.naa.org/technology/pressweb/index.html |title=Press web |publisher=Naa.org |access-date=12 December 2010 |url-status=dead |archive-url=https://web.archive.org/web/20080704154509/http://www.naa.org/technology/pressweb/index.html |archive-date=4 July 2008}}</ref> many newspapers have been undergoing what is known as "web cut down", in which the publication is redesigned to print using a narrower (and less expensive) roll of paper. In extreme examples, some broadsheet papers are nearly as narrow as traditional tabloids.

== See also ==
{{Portal|Contents}}
* [[Book size]]
* [[Continuous stationery]]
* [[Hole punch]] – filing holes
* [[Margin (typography)|Margin]]
* [[New Zealand standard for school stationery]]
* [[PC LOAD LETTER]]
* [[Paper density]]
* [[Photo print sizes]]
* [[Tiled printing]]
* [[Toilet_paper#Sheet_size|Toilet paper § Sheet size]]
* [[Units of paper quantity]] – ream, quire etc.

== References ==
{{reflist|refs=
<ref name="PWG">{{cite web|url=http://ftp.pwg.org/pub/pwg/candidates/cs-pwgmsn20-20130328-5101.1.pdf |title=IEEE-ISTO PWG 5101.1-2013 "PWG Media Standardized Names 2.0"}} [https://www.iana.org/assignments/ipp-registrations/ipp-registrations-4.csv Alt URL] <!--  "media, size name", "envelope name" --></ref>
}}

== Further reading ==
{{refbegin}}
* {{cite book |author-first=Arthur D. |author-last=Dunn |url=http://www.cl.cam.ac.uk/~mgk25/volatile/dunn-papersizes.pdf |publisher=Canada National Library |title=Notes on the standardization of paper sizes |location=Ottawa, Canada |date=1972}} (54 pages)
* {{cite book |author-first1=Max |author-last1=Helbig |author-first2=Winfried |author-last2=Hennig |title=DIN-Format A4—Ein Erfolgssystem in Gefahr |language=de |series=Beuth-Kommentare |publisher=Beuth Verlag |location=Berlin |date=1998 |isbn=3-410-11878-0}}
* [[International standard]] [[ISO 216]], Writing paper and certain classes of printed matter—Trimmed sizes—A and B series. [[International Organization for Standardization]], Geneva, 1975.
* International standard ISO 217: Paper—Untrimmed sizes—Designation and tolerances for primary and supplementary ranges, and an indication of machine direction. [[International Organization for Standardization]], Geneva, 1995.
{{refend}}

== External links ==
{{commons category|Paper formats}}
* {{cite IETF |title=Making Postscript and PDF International |rfc=2346 |author-last=Palme |author-first=Jacob |date=May 1998 |publisher=[[Internet Engineering Task Force|IETF]] |access-date=22 June 2012|ref=RFC2346}} Notably: About margin settings for using just the space common to both A4 and US Letter.
* {{cite web |url=http://ftp.pwg.org/pub/pwg/candidates/cs-pwgmsn20-20130328-5101.1.pdf |title=IEEE-ISTO PWG 5101.1-2013 'PWG Media Standardized Names 2.0'|ref=PWG}} <!-- https://www.iana.org/assignments/ipp-registrations/ipp-registrations-4.csv "media, size name", "envelope name"; https://www.iana.org/assignments/ipp-registrations/ipp-registrations.xhtml -->
* {{cite web |url=https://www.youtube.com/watch?v=mHeo62B0d0E | archive-url=https://ghostarchive.org/varchive/mHeo62B0d0E | archive-date=2021-11-03 | url-status=live|title=Paper Sizes Explained |author-first=Matt |author-last=Parker |author-link=Matt Parker |publisher=[[BBC]] Number Hub |type=YouTube video}}{{cbignore}}

{{ISO standards}}
{{Paper}}
{{Fractions and ratios}}
{{Typography terms}}
{{Authority control}}

{{DEFAULTSORT:Paper Size}}
[[Category:Book design]]
[[Category:Mechanical standards]]
[[Category:Paper]]
[[Category:Stationery]]
[[Category:Technical drawing]]