# Why is a pound 454 grams if water is 1g/mL? **URL:** \ **Category:** Factual Questions\ **Created:** [August 19, 2011, 8:00pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364 "2011-08-19T20:00:28Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![chaoticbear](https://avatars.discourse-cdn.com/v4/letter/c/f07891/32.png) [@chaoticbear](https://boards.straightdope.com/u/chaoticbear)\ **Post date:** [August 19, 2011, 8:00pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/1 "2011-08-19T20:00:28Z")
Even looking at the table for temperature vs density, I can’t reconcile the fact that 1 pint is 473 mL, and one pound is 454 g. Is the slightly-less-than 1g/mL really enough to cause such a difference? (slow day at the office) ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [August 19, 2011, 8:05pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/2 "2011-08-19T20:05:53Z")
Because [1 pint is _not_ 1 pound](http://en.wikipedia.org/wiki/Pint#Equivalence), contrary to the popular saying. ---
**Author:** ![gazpacho](https://avatars.discourse-cdn.com/v4/letter/g/6f9a4e/32.png) [@gazpacho](https://boards.straightdope.com/u/gazpacho)\ **Post date:** [August 19, 2011, 8:33pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/3 "2011-08-19T20:33:04Z")
> [@scr4](#): > > Because [1 pint is _not_ 1 pound](http://en.wikipedia.org/wiki/Pint#Equivalence), contrary to the popular saying. So not only is the pint not a pound except in the US it is not a pound in the US either. Another rule of thumb that is not helpful. They should change the name from “fluid ounces” to “fluid approximately ounces”. ---
**Author:** ![cjepson](https://avatars.discourse-cdn.com/v4/letter/c/a9adbd/32.png) [@cjepson](https://boards.straightdope.com/u/cjepson)\ **Post date:** [August 19, 2011, 8:39pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/4 "2011-08-19T20:39:57Z")
> [@gazpacho](#): > > So not only is the pint not a pound except in the US it is not a pound in the US either. Another rule of thumb that is not helpful. Actually, I’d say that in the US at least, it’s pretty much precisely what a rule of thumb should be – simple, easy to remember, and very close to being exactly right. ---
**Author:** ![njtt](https://avatars.discourse-cdn.com/v4/letter/n/ecd19e/32.png) [@njtt](https://boards.straightdope.com/u/njtt)\ **Post date:** [August 19, 2011, 8:43pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/5 "2011-08-19T20:43:58Z")
> [@cjepson](#): > > Actually, I’d say that in the US at least, it’s pretty much precisely what a rule of thumb should be – simple, easy to remember, and very close to being exactly right. Maybe if they dropped “the world around” bit, which is flat out false. ---
**Author:** ![grama](https://avatars.discourse-cdn.com/v4/letter/g/7cd45c/32.png) [@grama](https://boards.straightdope.com/u/grama)\ **Post date:** [August 19, 2011, 9:10pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/6 "2011-08-19T21:10:03Z")
Just go metric and move on with your lives 😛 ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [August 19, 2011, 9:14pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/7 "2011-08-19T21:14:58Z")
> [@njtt](#): > > Maybe if they dropped “the world around” bit, which is flat out false. Indeed. In Imperial “a pint of water weighs a pound and a quarter” ---
**Author:** ![samclem](https://avatars.discourse-cdn.com/v4/letter/s/a9a28c/32.png) [@samclem](https://boards.straightdope.com/u/samclem)\ **Post date:** [August 19, 2011, 9:44pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/8 "2011-08-19T21:44:02Z")
> [@Mangetout](#): > > Indeed. In Imperial “a pint of water weighs a pound and a quarter” But…it doesn’t rhyme. ☹ ---
**Author:** ![Ximenean](https://avatars.discourse-cdn.com/v4/letter/x/aca169/32.png) [@Ximenean](https://boards.straightdope.com/u/Ximenean)\ **Post date:** [August 19, 2011, 9:46pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/9 "2011-08-19T21:46:55Z")
It does in imperial pronunciation. ---
**Author:** ![Greg\_Charles](https://avatars.discourse-cdn.com/v4/letter/g/839c29/32.png) [@Greg\_Charles](https://boards.straightdope.com/u/Greg_Charles)\ **Post date:** [August 19, 2011, 10:26pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/10 "2011-08-19T22:26:00Z")
Grams measure mass and liters measure volume, so 1g/ml is only accurate for one density of water. I believe that’s water at 4C. Hotter or colder water would be less than 1g/ml. ---
**Author:** ![Cheshire\_Human](https://avatars.discourse-cdn.com/v4/letter/c/5f8ce5/32.png) [@Cheshire\_Human](https://boards.straightdope.com/u/Cheshire_Human)\ **Post date:** [August 19, 2011, 11:22pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/11 "2011-08-19T23:22:23Z")
Another reason the saying is “good enough” is that it is supposed to apply to dry stuff like sugar or flour, usually specified in pounds, and less dense than water. Also butter or lard, also less dense than water. It’s more nearly accurate for those, if you don’t have a scale. I attempt no justification for “the world around” bit, however. That always struck me as stupid since people living less than 100 miles from me when I was growing up used a different “pint” and I knew it. ---
**Author:** ![outlierrn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/outlierrn/32/3005_2.png) [@outlierrn](https://boards.straightdope.com/u/outlierrn)\ **Post date:** [August 20, 2011, 1:00am UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/12 "2011-08-20T01:00:12Z")
> [@grama](#): > > Just go metric and move on with your lives 😛 Word ---
**Author:** ![etv78](https://avatars.discourse-cdn.com/v4/letter/e/d78d45/32.png) [@etv78](https://boards.straightdope.com/u/etv78)\ **Post date:** [August 20, 2011, 1:07am UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/13 "2011-08-20T01:07:22Z")
So Alton was wrong? ☹ ---
**Author:** ![california\_jobcase](https://avatars.discourse-cdn.com/v4/letter/c/9d8465/32.png) [@california\_jobcase](https://boards.straightdope.com/u/california_jobcase)\ **Post date:** [August 20, 2011, 1:20am UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/14 "2011-08-20T01:20:04Z")
Alton couldn’t pronounce plantain, astaxanthin, or arthropod correctly. ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [August 20, 2011, 1:40pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/15 "2011-08-20T13:40:35Z")
An imperial gallon is 160 (fluid) ounces. A US gallon is 128 fluid ounces. However, they are not even the same ounces… Thanks to Wikipedia: > [@](#): > > In 1824 the British Parliament defined the imperial gallon as the volume of ten avoirdupois pounds of water. The gallon was divided into four quarts or eight pints. Each pint was divided into four gills or twenty fluid ounces. Thus, the mass of an imperial fluid ounce of water is one avoirdupois ounce (28.4 g) The US ounce is based on the earlier definition of one gallon equaling 231 cubic inches. This measurement at first glance does not seem to have any tie to mass, however it is believed[by whom?] to have come from a previous measure of a gallon as being 224 cubic inches (just 7 cubic inches less, both numbers being multiples of 7) which was used because it was the exact volume of 8 pounds of wine. A _ **real** _ gallon of water is 10 pounds. Can’t get any simpler than that. ---
**Author:** ![chaoticbear](https://avatars.discourse-cdn.com/v4/letter/c/f07891/32.png) [@chaoticbear](https://boards.straightdope.com/u/chaoticbear)\ **Post date:** [August 20, 2011, 3:47pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/16 "2011-08-20T15:47:45Z")
Oh no! I’ve been lied to! I had some free time doing some mind-numbing unit-dosing at work yesterday and no one there was able to help me. Thanks, SDMB! ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [August 20, 2011, 5:05pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/17 "2011-08-20T17:05:11Z")
> [@california\_jobcase](#): > > Alton couldn’t pronounce plantain, astaxanthin, or arthropod correctly. How do you mispronounce arthropod? Also, pronouncing plantain as it is spelled is not a mispronunciation, but a regionalism in the U.S. In fact, I have never heard it pronounce plan-tin in my entire life. ---
**Author:** ![california\_jobcase](https://avatars.discourse-cdn.com/v4/letter/c/9d8465/32.png) [@california\_jobcase](https://boards.straightdope.com/u/california_jobcase)\ **Post date:** [August 20, 2011, 6:50pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/18 "2011-08-20T18:50:57Z")
He said it “anthropod”, and I was raised in a time in which dictionary pronunciations were king. I have never seen a print dictionary with the “plan tane” pronunciation. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [August 20, 2011, 7:00pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/19 "2011-08-20T19:00:12Z")
> [@samclem](#): > > But…it doesn’t rhyme. ☹ A pint of water Weighs a pound and a quarter ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [August 20, 2011, 7:15pm UTC](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364/20 "2011-08-20T19:15:41Z")
In American pronunciation, “water” != “warter”. Though it’s closer than the rhymes you’ll find in a lot of poems and songs. [Next page](https://boards.straightdope.com/t/why-is-a-pound-454-grams-if-water-is-1g-ml/593364.md?page=2)