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Halfwidth and Fullwidth Forms (Unicode block)

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Halfwidth and Fullwidth Forms
(240 code points)
ScriptsHangul (52 char.)
Katakana (55 char.)
Latin (52 char.)
Common (66 char.)
Symbol setsVariant width characters
Assigned225 code points
Unused15 reserved code points
Unicode version history
1.0.0 (1991)216 (+216)
1.1 (1993)223 (+7)
3.2 (2002)225 (+2)
Unicode documentation
Code chart ∣ Web page
Note: [1][2][3]

Halfwidth and Fullwidth Forms is the name of a Unicode block U+FF00–FFEF, provided so that older encodings containing both halfwidth and fullwidth characters can have lossless translation to/from Unicode. It is the second-to-last block of the Basic Multilingual Plane, followed only by the short Specials block at U+FFF0–FFFF. Its block name in Unicode 1.0 was Halfwidth and Fullwidth Variants.[4]

Range U+FF01–FF5E reproduces the characters of ASCII 21 to 7E as fullwidth forms. U+FF00 does not correspond to a fullwidth ASCII 20 (space character), since that role is already fulfilled by U+3000 "ideographic space".

Range U+FF61–FF9F encodes halfwidth forms of katakana and related punctuation in a transposition of A1 to DF in the JIS X 0201 encoding – see half-width kana.

The range U+FFA0–FFDC encodes halfwidth forms of compatibility jamo characters for Hangul, in a transposition of their 1974 standard layout. It is used in the mapping of some IBM encodings for Korean, such as IBM code page 933, which allows the use of the Shift Out and Shift In characters to shift to a double-byte character set.[5] Since the double-byte character set could contain compatibility jamo, halfwidth variants are needed to provide round-trip compatibility.[6][7]

Range U+FFE0–FFEE includes fullwidth and halfwidth symbols.


Halfwidth and Fullwidth Forms[1][2]
Official Unicode Consortium code chart (PDF)
  0 1 2 3 4 5 6 7 8 9 A B C D E F
U+FF3x _
U+FF7x ソ
1.^ As of Unicode version 15.1
2.^ Grey areas indicate non-assigned code points

The block has variation sequences defined for East Asian punctuation positional variants.[8][9] They use U+FE00 VARIATION SELECTOR-1 (VS01) and U+FE01 VARIATION SELECTOR-2 (VS02):

Variation sequences for punctuation alignment
U+ FF01 FF0C FF0E FF1A FF1B FF1F Description
base code point
base + VS01 !︀ ,︀ .︀ :︀ ;︀ ?︀ corner-justified form
base + VS02 !︁ ,︁ .︁ :︁ ;︁ ?︁ centered form

An additional variant is defined for a fullwidth zero with a short diagonal stroke: U+FF10 FULLWIDTH DIGIT ZERO, U+FE00 VS1 (0︀).[10][9]


The following Unicode-related documents record the purpose and process of defining specific characters in the Halfwidth and Fullwidth Forms block:

Version Final code points[a] Count L2 ID WG2 ID Document
1.0.0 U+FF01..FF5E, FF61..FFBE, FFC2..FFC7, FFCA..FFCF, FFD2..FFD7, FFDA..FFDC, FFE0..FFE6 216 (to be determined)
N4403 (pdf, doc) Umamaheswaran, V. S. (2014-01-28), "Resolution M61.01", Unconfirmed minutes of WG 2 meeting 61, Holiday Inn, Vilnius, Lithuania; 2013-06-10/14
L2/17-056 Lunde, Ken (2017-02-13), Proposal to add standardized variation sequences
L2/17-436 Lunde, Ken (2018-01-21), Proposal to add standardized variation sequences for fullwidth East Asian punctuation
L2/18-039 Anderson, Deborah; Whistler, Ken; Pournader, Roozbeh; Moore, Lisa; Liang, Hai; Cook, Richard (2018-01-19), "24. Fullwidth East Asian Punctuation", Recommendations to UTC #154 January 2018 on Script Proposals
L2/17-362 Moore, Lisa (2018-02-02), "B.4.1 New Proposal to add standardized variation sequence for U+FF10 FULL WIDTH DIGIT ZERO", UTC #153 Minutes
L2/18-115 Moore, Lisa (2018-05-09), "Consensus 154-C17", UTC #155 Minutes, Add 16 standardized variation sequences based on L2/17-436R, for Unicode 12.0.
L2/19-055 Iancu, Laurențiu (2019-01-14), Proposed Changes in the Segmentation Property Values for Fullwidth Digits
L2/19-008 Moore, Lisa (2019-02-08), "B. Proposed changes in the segmentation property values for fullwidth digits", UTC #158 Minutes
1.1 U+FFE8..FFEE 7 (to be determined)
3.2 U+FF5F..FF60 2 L2/99-052 Freytag, Asmus (1999-02-05), The math pieces from the symbol font
L2/01-033 Karlsson, Kent; Freytag, Asmus (2001-01-16), Disunify braces/brackets for math, computing science, and Z notation from similar-looking CJK braces/brackets
L2/01-159 N2344 Ad-hoc report on Mathematical Symbols, 2001-04-03
L2/01-157 N2345R Karlsson, Kent (2001-04-04), Proposal to disunify certain fencing CJK punctuation marks from similar-looking Math fences
L2/01-168 Whistler, Ken (2001-04-10), Bracket Disunification & Normalization Hell
L2/01-012R Moore, Lisa (2001-05-21), "Disunifying Braces and Brackets", Minutes UTC #86 in Mountain View, Jan 2001
L2/01-223 Suignard, Michel (2001-05-23), Discussion of Issues Regarding Bracket Disunification
L2/01-184R Moore, Lisa (2001-06-18), "Motion 87-M21", Minutes from the UTC/L2 meeting, Reverse the decision made in motion 86-M6 not to disunify brackets.
L2/01-317 Suignard, Michel (2001-08-14), Bracket Disunification & Normalization
L2/01-295R Moore, Lisa (2001-11-06), "Bracket Disunification and Normalization", Minutes from the UTC/L2 meeting #88
L2/02-154 N2403 Umamaheswaran, V. S. (2002-04-22), "Resolution M41.1", Draft minutes of WG 2 meeting 41, Hotel Phoenix, Singapore, 2001-10-15/19
  1. ^ Proposed code points and characters names may differ from final code points and names

See also[edit]


  1. ^ "Unicode 1.0.1 Addendum" (PDF). The Unicode Standard. 1992-11-03. Retrieved 2016-07-09.
  2. ^ "Unicode character database". The Unicode Standard. Retrieved 2023-07-26.
  3. ^ "Enumerated Versions of The Unicode Standard". The Unicode Standard. Retrieved 2023-07-26.
  4. ^ "3.8: Block-by-Block Charts" (PDF). The Unicode Standard. version 1.0. Unicode Consortium.
  5. ^ "ICU Demonstration - Converter Explorer". demo.icu-project.org. Retrieved 7 May 2018.
  6. ^ "Halfwidth and Fullwidth blame".
  7. ^ "Conversion Data - Old location of the ICU User Guide".
  8. ^ Lunde, Ken (2018-01-21). "L2/17-436: Proposal to add standardized variation sequences for fullwidth East Asian punctuation" (PDF).
  9. ^ a b "Unicode Character Database: Standardized Variation Sequences". The Unicode Consortium.
  10. ^ Beeton, Barbara; Freytag, Asmus; Iancu, Laurențiu; Sargent, Murray (2015-10-30). "L2/15-268: Proposal to Represent the Slashed Zero Variant of Empty Set" (PDF).