From Wikipedia, the free encyclopedia
Jump to: navigation, search
WikiProject Measurement (Rated Start-class, Top-importance)
WikiProject icon This article is within the scope of WikiProject Measurement, a collaborative effort to improve the coverage of Measurement on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.
Start-Class article Start  This article has been rated as Start-Class on the project's quality scale.
Checklist icon
 Top  This article has been rated as Top-importance on the project's importance scale.
Wikipedia Version 1.0 Editorial Team / Vital (Rated C-class, Top-importance)
WikiProject icon This article has been reviewed by the Version 1.0 Editorial Team.
C-Class article C  This article has been rated as C-Class on the quality scale.
Checklist icon
 Top  This article has been rated as Top-importance on the importance scale.
Note icon
This article is Uncategorized.
Taskforce icon
This article is a vital article.

How old?[edit]

See for 1979 acceptance of L as well as l. Hotlorp 23:29 Feb 14, 2003 (UTC)

The year of 1901 cannot be right, can it? I thought the Imperial gallon being defined by so and so measure of water was inspired by the metric definition of a litre, so it must have been at the start of the 18th century -- Egil

You are right: the litre is older than 1901. See the current article. -- Heron


Added kilolitre - my water bills in Australia used to measure consumption in kilolitres. - David Gerard 12:54, Jan 28, 2004 (UTC)

Circular dependency?[edit]

Nothing depends ON litre, so no matter what litre depends on, there cannot be any circular dependency, can it? --Mormegil 10:21, 10 Aug 2004 (UTC)

Good point, removed this from the article. Paranoid 18:57, 20 Nov 2004 (UTC)

Reasons for redefinition[edit]

Does anyone know why the litre was redefined in 1901? It doesn't make any sense to me, when you had a perfectly good definition based on the metre. Paranoid 18:57, 20 Nov 2004 (UTC)

It was indeed rather senseless, IMHO, but the CGPM did finally come to their senses and "abrogate" that definition (that's how it is phrased in the legalese of their resolution).
Originally, it was intended that the gram should be the mass of a cubic centimeter of water; so obviously the length standards were constructed first. But then, way back in 1799, the original platinum cylinder known as the Kilogramme of the Archives was constructed by the French government to serve as the mass standard. Since then, the definition of the kilogram has never been officially based on water.
After the Metre Convention (or Treaty of the Meter) of 1875, the organizations known as the CGPM and BIPM were formed. They has a new set of international standards for the metre and the kilogram constructed, placing them in use in 1889. In constructing this new platinum-iridium International Prototype Kilogram and its siblings which serve as national standards, the target was the old French standard—not water.
But by then, in the late 19th century, people had been able to make better measurements of the density of water, at its maximum density and throughout the temperature ranges of liquid water, and were well aware of the discrepancies between the actual kilogram, and what it would have been if the 18th century French technicians had been able to carry out these measurements more precisely in constructing their kilogram.
Obviously, there were some users in the science who thought it was terribly important to have that exact relationship with water at its maximum density. So the CGPM let itself be talked into this hairbrained scheme of redefining the litre to make that true (I wouldn't call it that in the article, but am expressing my opinion of it here on the Talk pages).
Note that this is a flip-flop of the original intention of defining the unit of mass based on the cube of the unit of length. In 1901, they instead redefined the unit of volume based on the unit of mass.
Cubic centimeters, of course, remained the cube of the length units. So for a couple of generations or so, we students had to waste a lot of time learning that they were not the same thing as milliliters. Never mind that there had only been a handful of measurements in the history of the world where it ever made any difference.
There was, of course, a similar discrepancy in the construction of the original metre, from their very good but not as good as today's efforts to measure the meridian quadrant, and as a result there are actually 10.002 Mm from the equator to the poles, rather than the intended 10 Mm exactly. Fortunatly, the CGPM never got talked into any scheme to add another new length unit to use alongside the metre, but equal to 1.0002 m.
Note that I have removed an erroneous claim in the article as I found it that the intent in 1901 was that the 1901 definition would be the same as a cubic decimetre. It was well known that it would not, and that in fact was the entire purpose of that redefinition, to make it different from the cubic decimeter which for water never quite gets up to that 1.00000 kg level under one atmosphere of pressure, even at maximum density. Gene Nygaard 03:12, 13 Dec 2004 (UTC)

Symbol mL[edit]

CGPM in 1979 said:

considering further that in the future only one of these two symbols should be retained, invites the CIPM to follow the development of the use of these two symbols and to give the 18th CGPM its opinion as to the possibility of suppressing one of them.

The CIPM, in 1990, considered that it was still too early to choose a single symbol for the litre.

The United States National Institute of Standards and Technology recommends the use of the uppercase letter L.

Uppercase L has become the preferred and more common symbol in US & Canada. It only makes sense that the others (mL) use capital too - otherwise there's confusion.

Are there any standard bodies recommending lowercase be retained?

I'd say "the handwriting is on the wall" - there's not a chance in hell that lowercase will be the single symbol --JimWae 18:50, 2004 Dec 14 (UTC)

Medical fields find that using L is preferable. Less likely to misread a report of 1l in a column of data as meaning 11. I teach metrology often to students going into medical professions, and the current texts have all adopted L along with mentioning anecdotes of cases where the 1/l confusion caused interpretation errors.--Sturmde 19:42, 9 November 2005 (UTC)

Well, for me using lowercase l all the time, it was a big surprise that somebody uses a big L for the liter/litre? But this is actually a very small issue between english speaking people and others. The more confusing thing is that you guys are using decimal point as we are using decimal comma, and all texts and programs should to be able to make the conversations. In the spreadsheet world this is solved but with text editors one has to make the change manually. --Jabamula 21:14, 20 December 2005 (UTC)

I agree with Jabamula. The cited possible "confusion" is merely based on sloppiness. In handwriting the difference is obvious, in most fonts too, and if someone "causes confusion" by writing or omitting a unit on a form, then the form and/or the writer is sloppy. Having a regular system with small letters for all units makes much more sense. And why should the English-speaking people dictate a silly change for the rest of the world? It would be equally silly to say that the gram should be written with a capital G because the small g resembles a 9 too much. --Rhialto Sat 9 Aug 2008 18:57:35 CEST —Preceding unsigned comment added by (talk) 17:01, 9 August 2008 (UTC)

Not to mention that SI requires a space between the value and its unit, making any confusion a complete non-issue. Kolbasz (talk) 22:54, 31 October 2011 (UTC)

Capacity v. Volume[edit]

Capacity.... is the capacity to hold a certain volume. As you fill a container, the remaining capacity is lowered. TheFarg (talk) 04:57, 24 March 2012 (UTC)

Can anyone give a practical or commercial case in which the litre is used for solids? --JimWae 18:50, 2004 Dec 14 (UTC)

Certainly. Grain might flow, but it is not a fluid. Same goes for blueberries (where in the U.S., the 1 pint packages also include 551 mL right on the label, for example). Gene Nygaard 20:58, 14 Dec 2004 (UTC)
Here's another example, from

Comparison of specific strength of engineering alloys

Material Density


Yield Strength
Specific Strength
CP Titanium 4.51 105 250 - 450 50 - 100
Ti-6Al-4V 4.43 112 900 - 1100 200 - 250
Ti - LCB®® 4.79 110 950 - 1400 200 - 290
Carbon Steel 7.8 200 350 - 450 45 - 60
Aluminium Alloy 2.8 70 100 - 350 35 - 125
Gene Nygaard 21:18, 14 Dec 2004 (UTC)
The capacity of a garbage bag is not the measurement of a fluid. Sure, it is the volume of a fluid such as air which would fit into it. But that's not usually what we use our garbage bags for. Gene Nygaard 21:41, 14 Dec 2004 (UTC)

I guess it could be different in different countries, but we do not buy rice or wheat or or candy or aluminum by the litre in Vancouver - not retail, & I doubt wholesale too.

Blueberries & strawberries come in CONTAINERS with a certain mL capacity ( I notice you used mL too) & no weighing is then needed. Would anybody really expect they are getting 551 mL of blueberries without the air?

I think derived units for density using kg/L might stay current because it is an obvious way to compare to water that way.

I was taught litre was for capacity (and "fluids" & even small solids that flow that are not normally counted & usually get no indefinite article; e.g rice - not a rice, but yes an apple), m^3 was for volume. Though it is not a hard & fast rule, it is noteworthy enough, I think, to include somewhere in the encyclopedia (admittedly, not in the definition) - and I think clearer.

It's wrong. There is no distinction between capacity and volume in the metric system. Blaise 22:45, 23 May 2006 (UTC)

The Wikipedia isn't just a British Columbia project.
Look at any Canadian table of conversion factors for bushels (at least by anyone not smart enough to know that most of the bushels we use today are units of mass). What are the metric units used? What do we measure with bushels?
Google bushel hectoliter OR hectoliters OR hectolitre OR hectolitres OR hektoliter
The site tells us that

"Fresh BC blueberry packages include:

  • five and ten pound bulk cases,
  • and trays containing twelve one-pint
  • or twelve half-pint units and other sizes."
Of course, there are a couple of differences between your British Columbia blueberry boxes and mine in the United States:
  1. Those Canadian containers do not include the word "pint" or an abbreviation of it on the label.
  2. Those pint containers are 568 mL rather than 551 mL. That's because you use those dinky little litres instead of the hefty liters we use, isn't it?  :-)
That there are air spaces among the berries does not mean that you are measuring a fluid.
For wheat in Canada, the "test weight" (a measurement of bulk density, used as a quality factor) is still very often measured in pounds per U.S. bushel (rarely if ever per imperial bushel). But you also see it expressed in metric units, such as the "kg/hl" at
Yes, I used mL too. But I when I commented on your web page, what I said is that it is not good form to change someone elses "ml" to "mL' in Wikipedia. (Trying to achieve consistency within one article might be acceptable, not just flip-flopping from one to the other). For this particular article, and probably not any other, I think it would be a good idea to include both in all uses, but I'm not going to add that now.
Those density usages are quite relevant to the untruth of the limitation you claim.
Whoever the anonymous person was who deleted your statement about liters only being for fluids got it right. (Well, actually I'm just assuming you are the one who put it in there; it doesn't matter enough to me for me to go and confirm that--it's good riddance to misinformation in any case.) Gene Nygaard 01:25, 15 Dec 2004 (UTC)
In London (and possibly other parts of the UK) winkles - shellfish - were sold by the pint by street vendors. (talk) —Preceding undated comment added 12:06, 9 January 2014 (UTC)

OK, I'll agree "for fluids" was incomplete. It is also incomplete to leave it open to use litres for measuring quantities like solid metals.

Litres (& mL & kL) are used for things that are measured by the capacity of their containers - usually (but not exclusively) things that can be poured & that are non-count nouns (and usually in English anyway, get no indefinite article).

Water in a swimming pool would then be measured in litres, water falling over Niagara in m^3 - You will rarely see waterfalls measured in litres (though of course some will do so) -- the water is not in a container.

There may be exceptions to this too, but it is still noteworthy in an article about litres.

Only if it is true! There is no support at all within ISO 1000 or ISO 31 for any interpretation that litre and cubic metre measure different things. There *is* such a distinction in Imperial units, but the distinction simply does not exist in metric Blaise 22:59, 23 May 2006 (UTC)

Noting also: Many things that can be poured are sold by mass anyway.

A note was deleted which stated that the unit of volume in the SI is the m3. This should be reinstated. It is correct. The m3 is the derived unit of volume in the SI. NIST note on SI units

The liter is defined as one of the "Units outside the SI that are accepted for use with the SI." It is not, strictly speaking, a unit in the SI, and should not be represented as such. NIST note on units outside the SI.

I also find the statement above, "Litres (& mL & kL) are used for things that are measured by the capacity of their containers" to be very dubious. Can the author point to *any* publication by any authorative standards body that states this? I've never seen such a thing, and would find it hard to believe that any standards body created another unit of measure for volumes strictly based on intent. --Eliasen 03:08, 19 Dec 2004 (UTC)

You have said

  • The liter is defined as one of the "Units outside the SI that are accepted for use with the SI."

Whereas The 12th Conférence CGPM does not even define the litre, saying that it

  • declares that the word “litre” may be employed as a special name for the cubic decimetre,

so it does not DEFINE it at all, but gives an equivalancy in common use - it certainly does not define it "as one of the units outside the system", but further declares

  • that the name litre, although not included in the Système International d’Unités, must be admitted for general use with the System,

I've lived in a country that has used SI for 30 years. No current standards body created the litre - it is simply a unit in common use that "must be admitted for general use with SI - just like the minute and the day

The unit is not based on intent but on how the measurement is done.

If L (or mL or kL) are used, then (at least most likely) it has been measured by the size of the container it is in.

If kg are used, the expectation is that its weight or mass have been measured.

If m3 is used then (at least most likely) its dimensions have been measured -- OR its displacement.

I am really quite surprised that I cannot find a standards body that distinguishes capacity from volume -- What is the volume of a cubic container each of 6 sides a square of 11x11 cm, with each side 5 mm thick? What is its capacity? Remove 1 side and recalculate. There's some difference between volume & capacity, right?

I guess the standards bodies just do not want the added responsibility of defining a litre or its uses - so it would seem we cannot appeal to standards bodies but only to common usage Or perhaps it just is not their venue to make the distinction, maybe it's up to linguists or philosophers. --JimWae 05:38, 2004 Dec 19 (UTC)

As I understand it, there is no distinction in physics between capacity and volume units. Even in colloquial use, there is no real distinction. For example, people will accept that an engine 'capacity' can be described as 1.2 L (litre units) or 1200 cm³ (m³ units). It is interesting that we don't talk about a 1200 ml engine. Luggage and rucksacks are described in litres and so are car boots. However, aircraft containers for luggage are described in cubic metres. It is just a matter of size, history and application.
Ice cream and butter have similar consistency. Ice cream is described in litres in the UK, although butter is described in grams. Perhaps it is partly because ice cream is manufactured as a liquid. If I understand it correctly, medical people in the US used to measure liquid dose in 'cc' and had measuring devices with interior volume calibrated in cm³. I understand now that they use litre based units (mL) in the US (as does the UK).
The term 'capacity' means interior volume. The term 'volume' could be applied to interior or exterior volume. My thoughts in summary are:
1. People describe volume as 'volume', 'capacity' and 'displacement'.
2. People use units such as 'm³', 'litre', 'cc', 'ml', 'cm³', 'ton'.
3. You can sometimes link a description to a unit (displacement = 1100 cc) in a domain and a region but is more of an art than a science. Bobblewik 19:47, 21 September 2005 (UTC)
The U.K. sold ice cream in English units for many years before they ever started to use litres for this purpose. Just as in the United States, only even more so because they have smaller fluid ounces, the reason ice cream is sold by volume is that you get more "ounces" that way, because the density of ice cream is less than 1 oz/fl oz, even for the bigger U.S. fluid ounces. That's also why in the United States, evaporated milk is sold by the fluid ounce (i.e., by volume, with milliliters on the label as well), but sweetened condensed milk is sold by the avoirdupois ounce (i.e., by mass, with grams on the label as well). It has little or nothing to do with the texture and consistency of the product. Gene Nygaard 02:50, 16 October 2005 (UTC)
You are confused, JimWae. Standards agencies do define the liter. The 12th CGPM in 1964 did so, when it abrogated it's own definition from the 3rd CGPM in 1901, restoring it to the definition CGPM inherited when it was founded. Note also that though the liter is not an SI unit, and never will be, the CGPM since the introduction of SI has on three different occasions, IIRC, acted with respect to the non-SI liter. Gene Nygaard 03:21, 22 September 2005 (UTC)

The litre, as meant since the original metric system of 1791 was a unit of capacity, meaning what a container might carry. The volume of the contents will usually be less than or equal to the capacity of the container due to the spaces in between the water. For example, a 1 litre container might be full of berries and you could still pour water on it without overflowing the container.

The original system also had a named unit of volume which was the stere which is equivalent to a cubic meter, as it has a unit of area, the are which is often used as the hectare in the measurement of terrain, which in my city is about 1 city block == 1 hectare or about twice a football field, that is, a square 100 metres on a side.

So, since the litre remains with us mostly for historical reasons and as a shorthand for a cubic decimetre, let us keep its original intent in the definition, there was something else for volume and it was not the litre

--DevaSatyam 18:09, 15 October 2005 (UTC)

Standard litre per hour[edit]

Can someone explain me what is the difference between litres per hour and standard litres per hour. In fact, I am confused over the calculation of volume and pressure of gas with Boyle's law.

You need to provide a bit more context information to make your question meaningful. I suspect, that with "standard litre", you could mean a liter of some gas or liquid, where the volume is measured at some standard temperature and pressure (which one?). Markus Kuhn 1 July 2005 19:35 (UTC)

Yes, I needed to provide more info in fact I meant it STP. I am designing a high pressure skid for CO2 gas, where the gas is to be compressed to 350 bar pressure, and the same is to be injected in to extruder at a flow of 3 kg/h, the barrel of the extruder is having a temp. of 150 °C. I am using a gas booster for the same. I want to know whether the gas under compression will go in to liquid state, and secondly in the compress state how do I calculate the temp. at various pressure. Secondly what care has to be taken from safety point. Thanks for your reply. 22nd July'05 Hitesh Mody.

A phase diagram of CO2
Hm, sounds to me you are looking for a phase diagram of CO2 (and perhaps even for a chemical engineer as a consultant). Not really related to an encyclopedia entry on the litre ... Markus Kuhn 13:11, 22 July 2005 (UTC)

Why is it spelled "litre" anyway?[edit]

I'm just curious as to why the Commonwealth spelling of "liter" is "litre". I've noticed that if you said "litre" as it was spelled, it would come out as "lit-tree" instead of "lit-er". Why is that? --ApolloBoy 05:57, 25 September 2005 (UTC)

Notice also that if you pronounced "liter" as it seems to be spelt it'll come out as /li:t@(r)/ (in X-SAMPA). 26Oct05 i.e. (for most of us) it would be a homophone with lighter. Jimp 16Dec05

I wonder too why is it spelled "Litre" (British spelling I think) and not the common "Liter"? (same with metre-meter article) Yonir 11:30, 25 September 2005 (UTC)

Only one country uses the alternative spelling 'liter' the rest of the world (and the entire metric-using world) uses 'litre' — Preceding unsigned comment added by (talk) 16:35, 27 August 2015 (UTC)

English orthography is more etymological than phonological—as is French, where “litre” came from (although with a latinised Greek root). American English orthography tries to be a little bit more phonological. That works in the (probably most prominent) case of -re vs. -er or “gramme” vs. “gram”, but fails horribly with words like “night” vs. “nite” (should rather be something like “nait”), which is luckily not (yet) widely used.
Whether AE or BE is used in a Wikipedia article mostly depends on the main/first author(s), see the MoS. For litre this also applies to its symbol, which is either l or L. Christoph Päper 15:57, 25 September 2005 (UTC)
No, "nite" would be perfectly fine for "night" according to the rules of English orthography. Only the Americans don't officially use "nite". Jimp 26Oct05
On the other hand, one could wonder whether American English really deserves to have different spellings for measures which Americans refuse to adopt. ;) - toh 16:20, 3 October 2005 (UTC)
That's the best thing i've heard for ages, bravo! -- deanos {ptaaglek} 09:37, 4 October 2005 (UTC)
Typical American thing to do, isn't it? Refusing to adopt the metric system? I'm perfectly willing, but the rest of my country's not. Twilight Realm 03:21, 13 October 2005 (UTC)
Don't let anybody pull your legs, ApolloBoy and Yonir. The reason is so that we can tell those dinky little litres, where it takes 4.55 of them to make a gallon, from the he-man sized liters we have in the United States, where it only takes 3.79 of those "-er" units to make a gallon.  ;-) Gene Nygaard 04:15, 13 October 2005 (UTC)

Litre would be the original spelling; liter the U.S. reformulation (Noah Webster?). Same reason we spell battle, buckle, kettle, mettle the way we do. Michael Z. 2005-10-3 17:42 Z

Since America doesn't even use the measure, they should not dictate how it should be spelt. -- Dandelions 17:08, 30 May 2006 (UTC)

Litre would be litra, not lit-tree. 01:40, 4 November 2006 (UTC)

@ApolloBoy. It's because "Litre" was originally a French term, as the metric system was created in France. According to the SI, it's spelt litre. —Preceding unsigned comment added by Recipe For Hate (talkcontribs) 21:57, 1 March 2010 (UTC)

Greek (litron) --> French (litre) --> English (litre) --> U.S (litre/liter) ... And NOT litter ! ;-)

Christoph Päper claimed that "Whether AE or BE is used in a Wikipedia article mostly depends on the main/first author(s), see the MoS." This does not apply to "liter" versus "liter", at least for any article of a scientific nature, because the standard SI has only one spelling, which is litre. —DIV ( (talk) 10:44, 20 June 2008 (UTC))

To Gene, your comment is stupid because a litre is a standerd size no matter how its spelt whilst an Imperial gallon is bigger than a US gallon so your whole 'Mines bigger' is wrong. American English is different from British English mostly for two reasons, when the languages where codified America was more puritanical (Which is why they have tidbit instead of titbit and because Webster (I believe it was him but it could be someone else) chose to write alot of words differently because the US was isolationist at the time and it served the purpose of making thing aukward.( (talk) 23:49, 25 August 2008 (UTC))

Stupid as Gene intended thus the ";-)". JIMp talk·cont 19:21, 16 August 2009 (UTC) in norway, sweden denmark and estonia it is spelled liter(liiter in estonia though). it is easy to check how many countries spell it in the different ways just by looking at the articles on wikipedia. both spellings is international technically and as such i suggest changing the article. (talk) 09:35, 21 September 2016 (UTC)

Merge with mL[edit]

As I was finding the template to merge the millilitre article with this one, someone else went ahead and did it. That surprised me. But anyway, the mL article was almost the same as this one, but there may have been some small details in it that should be included in this one. Could someone check? Twilight Realm 03:19, 13 October 2005 (UTC)

mL vs. cm3[edit]

Isn't a millilitre the same as a cubic centimetre? This should be mentioned somewhere, but as I'm not positive, I'm not going to do anything now. Twilight Realm 03:19, 13 October 2005 (UTC)

They weren't, when I first learned about them. Lot's of effort was wasted teaching a trivial difference, just because some fools insisted on there being something magic about water at its maximum density and standard pressure. They are the same now, however. Gene Nygaard 04:11, 13 October 2005 (UTC)

So a liter is 1,000 cubic centimeters?[edit]

So a liter is 1,000 cubic centimeters? That's a lot. How come then, when you buy a one-liter soft drink, the bottle isn't 1,000 centimeters long by 1,000 centimeters wide by 1,000 centimeters thick? Wiwaxia

Because you've confused "1000 cubic centimeters" with "1000 centimeters cubed." A liter contains one thousand little cubes, each little cube being one centimeter on a side. You could stack them in a larger cube ten centimeters on each side, or in a line one thousand centimeters long but only one centimeter wide. Bryan 00:28, 9 January 2006 (UTC)
It's actually very simple math. If we take your case of 1000 cm by 1000 cm by 1000 cm, that would be: 1000 cm * 1000 cm * 1000 cm = 1000000000 cm³. Just multiply the numbers and the centimetres. The cubic measure also implies that it takes 1000 cm³ to be equal to 1 dm³, whereas normally you'd only need 10 cm to make 1 dm. --Ajunne 13:42, 17 September 2006 (UTC)
1 l = 1 L
= 0.001 m³ = 1 dm³ = (10 cm)³ = 10³ cm³ = 1000 cm³
≠ (1000 cm)³ = 1000³ cm³ = (10 m)³ = 1 dam³ = 1000 m³

277.13 K is NOT room temperature![edit]

0 C=273.15 K, so 277.13 is 3.98 C or approximately 4 C (see wikipedia Kelvin page). I edited out "room temperature" (normally 20-22 C or 293.15-295.15 K) and replaced it with "4 C".

What does this have to do with liters? 23:23, 2 October 2006 (UTC)
Water is unusual in that it expands both when cooled and heated. (Which is why ice cubes float--they're less dense than water.) 4 C is the temperature at which it takes up the least volume per unit mass. So at 4 C, 1kg of water is exactly 1 litre, which is exactly 10cm3, and that baseline is used to derive much of the rest of the metric system. --HKMarksTALKCONTRIBS 00:48, 3 October 2006 (UTC)
At approximately 3.98 °C, water is at its most dense at standard (atmospheric pressure). Note that this is not necessarily true for all pressures - according to - at pressures around and above 200 MPa, there is no longer a density maximum. Please note, also, that the Celsius scale of temperature uses degree symbols - if you leave them out, you will be referring to Coulombs. WLD 17:03, 3 October 2006 (UTC)
Yeah, but you know, they're just a pain in the tush to type just for a talk page :P --HKMarksTALKCONTRIBS 19:28, 3 October 2006 (UTC)
Alt+0176 gives the '°' symbol (at least on a PC). (talk) 16:47, 22 February 2012 (UTC)

Proposed WikiProject[edit]

Right now the content related to the various articles relating to measurement seems to be rather indifferently handled. This is not good, because at least 45 or so are of a great deal of importance to Wikipedia, and are even regarded as Vital articles. On that basis, I am proposing a new project at Wikipedia:WikiProject Council/Proposals#Measurement to work with these articles, and the others that relate to the concepts of measurement. Any and all input in the proposed project, including indications of willingness to contribute to its work, would be greatly appreciated. Thank you for your attention. John Carter 21:05, 2 May 2007 (UTC)

Ugly Table[edit]

Can someone please change the stupid looking greyed out table to be less stupid and ugly looking? Thanks. 00:32, 27 June 2007 (UTC)

I completely agree! Also, are there 2's all over that table when there should be 3's, or is that just my monitor? (It is supposed to be cubic after all)

A picture of a litre?[edit]

I came to this page hoping for a picture of a litre. Can anyone whack a picture of a 1 litre water bottle on this page to save time for the future? It's also a good visual reference of a litre volume. (something like THIS) —Preceding unsigned comment added by (talk) 00:40, 30 October 2007 (UTC)

Pictures are nice, but it's not easy to tell how big that bottle is without having other objects in the picture. —Preceding unsigned comment added by Bugmenottoday (talkcontribs) 12:59, 22 March 2009 (UTC)

Hectolitre directs here[edit]

According to, hectolitre = a metric unit of volume or capacity equal to 100 liters. So hectolitre should not redirect here, but instead explain the = 100x thing. Or am I wrong? (Ark25 (talk) 22:42, 1 June 2008 (UTC))

Air is a fluid[edit]

  • and so it is NOT unusual to use litres to measure "empty" space --JimWae (talk) 06:25, 17 August 2008 (UTC)
  • it is also not at all unusual to use litres for containers --JimWae (talk) 06:28, 17 August 2008 (UTC)

Simple conversion[edit]

I came to this page to double check myself on a simple conversion and found it nowhere.

How many ounces are in a liter? That seems like one of the most obvious conversions that should be here. —Preceding unsigned comment added by RazorDog (talkcontribs) 17:58, 9 January 2009 (UTC)

Which ounce? There are 35.195 fluid ounces in a litre, but it's not possible to convert between litres and Avoirdupois/Troy ounces because litres are a unit of volume and those ounces are units of weight. -- (talk) 00:14, 21 January 2009 (UTC)
Depends on what ounce you want 1 litre ≈ 35.1950797279 imperial fl oz ≈ 33.8140227018 US fl oz. JIMp talk·cont 20:41, 16 August 2009 (UTC)

ml in common US measure[edit]

I got to this article by clicling a link "ml" I think it was. I needed to know what one was since all I know is teaspoons,tablespoons,and onces as these are the measures used in the USA.There is no such info in the article. This article would be vasly more usfull to those of us in this position if there was a simple table showing these values. Thank you!BrianAlex (talk) 23:32, 5 June 2009 (UTC)

I added to the rough conversions section -- which would have helped you a bit even before my additions. --JimWae (talk) 01:28, 6 June 2009 (UTC)

Cubic centimetre non-SI?[edit]

"The most commonly used is the millilitre, defined as one-thousandth of a litre, and also often referred to using the non-SI name of 'cubic centimetre'."

I don't understand why the cubic centimetre is said to be a "non-SI name". The centimetre is an SI unit for length so therefore the cubic centimetre is an SI unit for volume. Can someone explain why cm3 is said to be non-SI?

  • I fixed it, thanks --JimWae (talk) 00:28, 18 December 2009 (UTC)
It's a grey-ish area - the most strict interpretations of SI are based on a system of powers of 3. Therefore, m3 are an SI unit, as would km3 and mm3, as they're based on powers of plus and minus 3, respectively. In a sense, cm3 are a non-SI derivation (-2), based on an SI unit.
Or, to put it another way, from Non-SI_units_accepted_for_use_with_SI, "...either the SI accepts their use as being multiples or submultiples of SI-units, or they have important contemporary application..." This is backed up in a number of other places in the article too. It probably fits under This Section, although it's not really used that commonly...
On the assumption that the above answers your question, I'll make an edit to restore the original statement, although I'll avoid a straight reversion, due to the age of your change. GGdown (talk) 15:58, 12 April 2011 (UTC)


Liter, libra and lira have the same etymology: & Böri (talk) 12:02, 3 February 2010 (UTC)

Merger of Litres per minute[edit]

The article Litre per minute does not contain any useful information. I woudl have no objection to its text being replaced by a redirection. However I think that a redirection to cubic metres per second would be more appropriate. Martinvl (talk) 14:35, 27 July 2010 (UTC)

Revocation of 19 November 2011[edit]

Please discuss these changes at Wikipedia talk:WikiProject Measurement#Changes to the ledes of many SI-related articles. Martinvl (talk) 18:34, 19 November 2011 (UTC)

Weight of a liter / litre is NOT 1 kg[edit]

In the lede it says: "One litre of liquid water has a mass of almost exactly one kilogram, due to the gram being defined in 1795 as one cubic centimetre of water.[3]" However, when I drilled some wells a few years ago I found that a cubic metre of water - that should weigh 1 tonne / 1,000 kgs - actually weighs about 910 kgs. My hydrologist said that it surprises most people, because the supposed beauty of the liter is that it weighs 1 kg - except it doesn't ... (talk) 17:09, 13 December 2011 (UTC)

A citation would be nice. Every steam table and table of densities of water I've seen always gives numbers around 0.99XX kg/l for pure water at room temperature. --Wtshymanski (talk) 18:56, 13 December 2011 (UTC)
The original definition stated that the temperature was that of melting ice - I have modified the lede accordingly. BTW, I bet that your water was not that cold when you drilled those holes - also what impurities were in the water?. Martinvl (talk) 16:21, 15 December 2011 (UTC)
The reason for the difference is much simpler than that. The kilogram was originally intended to be the mass of 1 litre of water at maximum density (i.e. at 4°C). To this end a cylinder made from platinum/iridium alloy was constructed as a physical standard and held in Sévres in France. As the precision with which it was possible to measure such quantities was improved, it was subsequently found that the cylinder was 28 parts per million too large. To this day 1 kilogram of water occupies 1.000028 litres. Or, if you prefer, 1 lire of water has a mass of 0.99927 kilogrammes.
The term 'litre' is not an official SI unit, though the SI system does state that the term 'litre' may be employed informally in place of 0.001 cubic metres. (talk) 16:37, 22 February 2012 (UTC)

Base unit??[edit]

I am consulting a chemestry professor right now and he says that the base units for a litre is 10-3 x m3. Does anyone know what exactly this means?? And can anyone verify that this statement is true???Slipknotissic (talk) 01:46, 11 January 2012 (UTC)

If he is using the language of SI, then he should not be using the term "base unit". He is however spot on if what he is really saying is that 1 L = 10-3 m3. This is easy to verify because a litre is equivalent to the volume of a cube with sides of 0.1 m and 0.1 x 0.1 x 0.1 = 0.001 = 10-3. Martinvl (talk) 16:27, 13 January 2012 (UTC)
There are seven SI base units: all other SI units are SI derived units. The litre is not a base unit: it is derived from the meter, which is a base unit. When performing a dimensional analysis of an equation, it is often a good idea to convert all units to base units, and the equation L=10-3 x m3 is the conversion factor for a litre. -Arch dude (talk) 14:22, 14 January 2012 (UTC)
Almost right. It is not even an official derived unit in the SI system precisely because it is not a derived unit. The SI system unit of volume is the cubic metre (metre is a fundamental or base unit). However, the SI system does permit the informal use of the litre to represent 0.001 cubic metres. (talk) 16:42, 22 February 2012 (UTC)
To be really pedantic, the litre is one of the Non-SI units mentioned in the SI. It is still converted to SI base units using the substitution L=10-3 x m3 .-Arch dude (talk) 22:27, 9 November 2012 (UTC)
The kilogram(me) is the standard SI unit for mass; the gram(me) is derived. See the CGS System. Si Trew (talk) 12:25, 18 February 2014 (UTC)


I see no reason to make the very 1st thing said about the litre is the unsourced claim that it is sometimes abbreviated as LTR. Saying this does belong in the article (as it can be found as usage in advertising), but it does not merit being the first thing said--JimWae (talk) 22:42, 6 March 2012 (UTC)

Why play it down - we usually put all that stuff at the very start - it should be bold too as a synonym in this context. -- de Facto (talk). 22:52, 6 March 2012 (UTC)

Why play it ABOVE the two official symbols, making things even more complicated? The official symbols need development before readers latch on to an abbreviation used primarily in advertising. This is further complicated by the existence of the non-SI lower-l-script symbol. Though not an SI unit, the SI body deliberates on what symbol to use for it (and others)--JimWae (talk) 23:04, 6 March 2012 (UTC)

Possible Vandalism[edit]

If the Talk page is the wrong section for this, sorry, but I'm not sure where to put this or whether to revert it or not. The second sentence of the second paragraph contains this wonderful snippet:

The original French metric system used the fat bastard as a base unit,

Something tells me this isn't meant to be there.

--Stirlitz the Russian Spy (talk) 04:34, 22 August 2012 (UTC)

I too noticed this little snippet. It is there without refernces or notes and a (semi) thorough online search has yelded no credible sources for this statement. It would be fodder for some humorous commentary if it was true, unfortunately I believe the fat bastard note is untrue.

Gobits01 (talk) 17:09, 23 August 2012 (UTC)

— Preceding unsigned comment added by (talk) 17:06, 23 August 2012 (UTC)

Reinstatement of 9 October 2012[edit]

I have reinstated the removal of so-called spam plus pictutre that was done last night.

As regards the picture - if a better picture exists, please use it, if not leave the existing picture where it is. A significant nubmer of readers can relate to that picture and it give an indication of the size of a litre.

As regards the possibility of spam - again, if better references exist, please add them. Just removing existing references without putting anything in their place is just that - removing references which comes very close to vanadalism. Martinvl (talk) 07:54, 9 November 2012 (UTC)

I have tidied up a few links - removed some obviously dead links and replaced one of two with more appropriate links. Martinvl (talk) 10:11, 9 November 2012 (UTC)
They're low value links and appears to have been added to drive traffic to those site. WP:REFSPAM It has been established that litre is a unit of volume, for which it maybe used to convey the volume of liquid, as well as space. The addition of links add very little value. Addition of personal website don't add more value than simply leaving it cited. The reason to avoid adding a list of examples is also explained there. There's no greater in citing each and every or adding many examples once we establish what litre can be applied for. Why not list websites that sell boxes, toilets (tank capacity expressed in litre), car dealers, (interior space in litres) and so on and on?Cantaloupe2 (talk) 15:00, 9 November 2012 (UTC)
1> The refs were originally added because other editors contested such usage. Perhaps, tho, we can agree to comment out the refs with <!--- ---> , thus keeping them nearby in case they are again contested. However, I still prefer just to keep them as refs. Unfortunately, sometimes lesser value refs are needed just to prevent petty-minded or silly objections, and thus free editors from needless patrolling & discussions. 2> AND, the list does NOT give brand names. 3> The picture gives size relative to a human hand, so does add value. Perhaps something other than an alocoholic beverage could be found, tho. UNtil then, keep the photo. --JimWae (talk) 20:51, 9 November 2012 (UTC)

Why is spelled litre instead of liter it should be liter because America is the best!!!!!!!! — Preceding unsigned comment added by (talk) 00:59, 25 November 2012 (UTC)

1kg = 1 litre of water at melting point of ice[edit]

My understanding is that a litre of water is 1kg at 4°C, not at "melting ice" as it previously said. The statement referenced a personal website in French. We need more authoritative reference in English so we can verify it. this source suggests what I was saying. Cantaloupe2 (talk) 22:21, 7 December 2012 (UTC)

In the lede, it is appropriate to say (somehow) that the litre is related to the gram, and that this relation dates from 1795. We can provide a more nuanced relationship later int he article, but the basic relationship is (in my opinion) fundamental and belongs in the lede. Of course, I'm just one editor, so we should discuss this here and reach a consensus. I am very happy to work with another editor who actually cares about precision. -Arch dude (talk) 02:01, 8 December 2012 (UTC)
You went ahead and reverted before you replied. See the page [[1]]. That is based on an obsolete definition that is no longer in use. I've provided a fairly credible reference that is in English that dissent from some person's homepage written in French, which presents difficulty for verification for English readers. Cantaloupe2 (talk) 02:04, 8 December 2012 (UTC)
No problem. I think we need something in the lede that relates the litre to the gram. If you do not agree, please reply. If you do agree (or if you are neutral) please recommend an alternative. In my opinon (I am only one editor) the linkage occurred in 1795 as evidenced by the ref. Yes, we know that the definition has changed, but those refinements do not relate to the historical relationship of litre to gram. -Arch dude (talk) 02:18, 8 December 2012 (UTC)
I think we should use something other than a personal page as reference, and drop "melting point of ice". Adding to it makes it incorrect, yet adding "3.94°C" makes it too complex for casual use. Thoughts? Cantaloupe2 (talk) 02:31, 8 December 2012 (UTC)
The website contains a transcript (not summary) of the law that was passed in 1795. The only question is whether or not the transcript is accurate. No doubt other references canbe found, but lets not just ditch this reference until a better one is found.

Commercial sites and citations[edit]

I have reinstated the link to a commercial site which advertises rucksacks in litres. We are caught between the devil and the deep blue sea. Some editors are going to whinge because there is no citation and others are going to whinge if a commercially-oriented citation is supplied. I think that it is better to have a citation from a commercially-oriented site than to have no citation. Of course if somebody is able to provide a citation from a non-commercial site, then so much the better, but until somebody can do that I am going to all that I can to keep this citation in place. Martinvl (talk) 11:04, 15 February 2013 (UTC)

That whole section is flawed, and needs replacing. If we are saying that the capacity of rucksacks or microwaves are measured in litres then we need to say that, and support it with sources saying just that, and not just link to cherry-picked specific proprietory catalogues which happen to use litres. That is not allowing the reader to verify the claims being made, it is just pointing him to one example - there is a very important difference. (talk) 11:29, 15 February 2013 (UTC)


Can someone please check the table: I don't think a nanolitre is equivalent to a million microlitres, which is what it says. Surely, it is a thousand times smaller than a microlitre? 1000 nl = 1microlitre. I think the table needs carefully checking and amending. thanks Peter morrell 07:02, 1 June 2013 (UTC)

Liter is the preferred spelling, favored over litre roughly 147 to 62[edit]

Google hits, July 4, 2013:

Liter: "About 147,000,000 results"

Litre: "About 61,800,000 results"

This article used UK spelling, not American spelling. Population of the UK + Australia + Canada is about 100 million. Population of the US is about 300 million. We would therefore expect the use of "Liter" to exceed the use of "Litre" by a factor of 3:1, but under WP:ENGVAR the variety of English in use must be respected. Martinvl (talk) 15:49, 4 July 2013 (UTC)
Couldn't variety be respected just as well by naming the article by the far more commonly used and searched spelling, with the less-common British spelling introduced in a first-sentence parenthetical?
There is already a redirect from liter to this article, and the situation is described in the first two sentences. WP:ENGVAR does not call for a vote. A change to "liter" will require a strong consensus among the editors. I for one am strongly in favor of retaining "litre," Primarily because it is the official spelling of the international standards body. -Arch dude (talk) 22:04, 4 July 2013 (UTC)

Millilitre needs its own section, for handy direct linking when clarifying measurements in text of other articles, e.g., drug dosage[edit]

Millilitre needs its own section, for handy direct linking when clarifying measurements in text of other articles, e.g., liquid IV bolus or results of laboratory tests of blood.

A clear explanation and a visual of a millilitre dose would be quite valuable, in contrast to the table here.

milliliter and millilitre both link to the appropriate section. I thought the whole point of "metric" is that it should be easily understandable. I still measure things in furlongs per fortnight but it would seem perfectly intelligible just as it is. Where else would you redirect it? Si Trew (talk) 12:30, 18 February 2014 (UTC)


NebY, Take a look at what you added back in. It is basically meaningless. How is it relevant to the definition of a letre?

I am One of Many, you removed material from the Definitions section with the comment "WP:OR and incorrect". Are you now resiling from that and instead claiming that taht material is meaningless and irrelevant? That is a very different claim and I would welcome an explanation of your original " WP:OR and incorrect" comment. I am also puzzled that you would call a brief clear statement defining the liter in terms of cubic metres and cubic centimetres as meaningless and question its relevance. Please can you explain? I am also wondering if there is a reason you spelt litre "letre" here and on my talk page. NebY (talk) 07:22, 22 July 2013 (UTC)


The article features a quite strange picture about Oktoberfest, where 1-litre beer mugs are used. I find this a totally arbitrary choice, which may only serve as an advertisement of Oktoberfest. When I deleted the picture, user Martinvl put it back with the text that it was an "earlier consensus" and it was "the best depiction of a litre to date". I do not know who reached this consensus, but it is highly controversial whether a 1-litre beer mug from Octoberfest is the best possible depiction of a litre. First, I do not know why do we need such an illustration, but if we do, why do we advertise an event with this. There could be many more much better illustrations, for example, in most European countries milk is sold in 1 litre boxes/bottles. As there are much more people who drink milk from such 1-litre packages than those who attend Oktoberfest, it would be a much better illustration. There should be easy to find similar examples, which do no advertise an event, as there are very many items that come in 1-litre packages. KœrteFa {ταλκ} 11:16, 27 July 2013 (UTC)

I put the Oktoberfest picture initially. I looked through Wikimedia Commons for a suitable picture - the criteria being an object that held one litre and some other object with which to compare it. This picture shows one litre beer mugs alongside human hands. Of course, if you can find (or take) a picture of a litre container with some object against which it can be referenced in all English-speaking countries, please do so. However, until you have a replacement, please leave the current picture where it is. Martinvl (talk) 18:38, 27 July 2013 (UTC)

Powers of 10 not divisible by 3[edit]

The article states: "In European countries where the metric system was established well before the adoption of the SI standard, there is still carry-over of usage from the precursor cgs and MKS systems."

I have not found anything in the offical SI standard that says that says that centi-, deci-, deka-, and hecto- are deprecated. As far as I can tell, the standard treats them all equally. There might be some national standards or institutional standards that seek to avoid these prefixes, but surely, it shouldn't be surprising that other nations don't heed these. Someone should probably fix that. 08:33, 16 November 2013 (UTC) — Preceding unsigned comment added by (talk)

This is entirely without references, but "decilitre" is used very commonly in Hungary (e.g a small glass of beer will be 3 dL). In the UK centi- seems to be going out and for most measures of flat pack furniture etc it is done to the millimetre, which is a bit of overprecision, so a kitchen cabinet will be 600 mm rather than 60 cm wide. Hecto, I have never heard in the UK, in particular a hectare nobody says, instead acre which is about 2.5 x 2.5 a hectare. It probably varies from country to country.
In Greece understandably, at least on the signs, they use "µ" (Greek letter mu. M) to abbreviate metre. What they do when they want to differentiate a millimetre from a micrometre, I don't know.
That's the pleasure of a uniform system isn't it. :-) Si Trew (talk) 12:44, 18 February 2014 (UTC)
I always find it odd when an editor says "someone should probably fix that". I thought on the main page it said, "This is Wikipedia, the free encyclopedia, that anyone can edit". Si Trew (talk)
Again, the powers of ten (you mean that in engineering it goes 10-6, 10-3, 100, 103, 106 and so on) I believe are mostly just the de facto standards used in engineering. (Declaration of interest: I am a member of an engineering professional trade organsation, the Institution of Engineering and Technology). I agree, it is not de jure fact that these other units are deprecated, but just de facto. Si Trew (talk) 16:20, 18 February 2014 (UTC)

'International' Spelling[edit]

The opening sentence

'The litre (International spelling as used by the International Bureau of Weights and Measures) or liter (American spelling)'

is truly cringe-worthy. I have no idea what an "International spelling" is... and that it hides the underlying link to American vs British English spelling differences seems to highlight an abuse here.

This is complicated but well explained in the body of the article.

There is nothing wrong, and everything right, with simply stating "Spelling as used by the International Bureau of Weights and Measures", and leave the situation to be explained in the article.

Grow up Mr. Yank, 'litre' is the original spelling. Something which you lot can't handle. Is it too European for you?

There's indeed nothing international about language. "Litre" just happens to be both French and British English spelling (where France happens to be the origin of the SI units), while "liter" is American English spelling. In other languages, we use other spellings. Like we also use "liter" in African, Dutch, Danish, German, Norwegian, Slovenian, Swedish. And how can "litre" be called international when other languages use "litro" (Italian, Spanish), "litra" (Finnish, Hungarian), Litr (Czech, Polish) or even "Λίτρο" (Greek) and "لتر" (Arabic). Names of units aren't standardised. They are translated according to the language used in the region, and spelled according to the spelling rules of that language. I can't help that English doesn't have a uniform spelling (unlike almost all other languages named), but "litre" is no more international than "لتر". --Sanderd17 (talk) 10:25, 25 January 2016 (UTC)

I presume it refers to the SI (Système international) spelling, which was internationally agreed. Quit whining, there aren't many Wikipedia pages with a non-US spelling, I think you lot do pretty well on the pages:population ratio!