Imperial pint

The pint /ˈpaɪnt/ ( listen ) (abbreviated as "pt" or "p") is a unit of volume or capacity in both the imperial and United States customary measurement systems. In both of those systems it is traditionally one-eighth of a gallon, Imperial or U.S., although measuring a different amount of liquid (an Imperial pint equals roughly 568 millilitres, or 20 Imperial fluid ounces; a U.S. pint equals roughly 473 millilitres, or 16 U.S. fluid ounces). The British pint is thus about 20% larger than the American pint (the two systems are not the same). Almost all other countries have standardized on the metric system. The size of what may be called a pint varies depending on local custom.

The imperial pint (≈ 568 ml) is used in the United Kingdom and Ireland and to a limited extent in Commonwealth nations. In the United States, two pints are used: a liquid pint (≈ 473 ml) and a less-common dry pint (≈ 551 ml). Each of these pints is one-eighth of its respective gallon, but the gallons differ and the imperial pint is about 20% larger than the US liquid pint. This difference dates back to 1824, when the British Weights and Measures Act standardised various liquid measures throughout the British Empire, while the United States continued to use the earlier English measures. The imperial pint consists of 20 imperial fluid ounces and the US liquid pint is 16 US fluid ounces, making the imperial fluid ounce about 4% smaller than the US fluid ounce.

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