Imperial Pints to US Fluid Ounces (pt (UK) to fl oz)

1 imperial pint equals 19.21519881 US fluid ounces (rounded).

1 imperial pint = 19.21519881 US fluid ounces

How to convert imperial pints to US fluid ounces

To convert imperial pints to US fluid ounces, multiply the number of imperial pints by 19.21519881. The factor is rounded to 10 significant digits. To go the other way, multiply US fluid ounces by 0.05204213654 (rounded).

US fluid ounces = imperial pints × 19.21519881

Example: 10 imperial pints = 192.1519881 US fluid ounces.

Pints, quarts, gallons and fluid ounces differ between the US and the UK. Units are labeled 'US' or 'imperial' to avoid confusion.

About these units

Imperial Pint (pt (UK))

Imperial (British)Current unit

Exactly 568.26125 mL (20 imperial fluid ounces). The pint of beer and milk in the UK and Ireland.

The imperial pint derives from Parliament's 1824 decision to replace Britain's assorted gallons with one defined by ten pounds of water at 62 degrees Fahrenheit. A pint is one eighth of that gallon and holds 20 imperial fluid ounces, or exactly 568.26125 milliliters. The word reached English from French pinte, which in modern French now means half a liter, while Canadian French uses it for the imperial quart.

That pint is about 20 percent larger than the US liquid pint of 473 mL, so a pint in Dublin or London buys noticeably more beer than one in Chicago. When Britain metricated, the pint was kept for draught beer and cider and for milk in returnable bottles, and draught beer has to be served in measured, stamped glasses. Culturally the pint is more than a measure: it is shorthand for a night at the pub.

1 imperial pint = 0.56826125 liters (exactly).

Sources: Wikipedia: Pint; UK Weights and Measures Act 1985, Schedule 1

US Fluid Ounce (fl oz)

US customaryCurrent unit

One 128th of a US gallon, 29.5735 mL. Not the same as the weight ounce, and about 4% larger than the imperial fluid ounce.

Fluid ounce began as an attempt to link volume to weight: the volume occupied by one ounce of some substance, such as wine in England or water in Scotland. Definitions varied by region and by liquid. When Britain defined its imperial gallon in 1824 as the space of ten pounds of water, the imperial fluid ounce came out so that an ounce of water weighs about one avoirdupois ounce. The US fluid ounce followed a different path and comes from the older wine gallon.

The US fluid ounce is exactly 1/128 of a US gallon, 29.5735295625 milliliters, about 4 percent bigger than the imperial one at 28.4130625 milliliters. American nutrition labels use yet another figure, treating one fluid ounce as 30 milliliters, a convenient rounding for serving sizes. The name is a trap, because a fluid ounce measures space while a weight ounce measures mass. A US fluid ounce of water weighs a bit more than an ounce of weight, while a fluid ounce of honey weighs considerably more.

1 US fluid ounce = 0.02957352956 liters (approximately).

Sources: Wikipedia: Fluid ounce; NIST SP 811, Appendix B.8: conversion factors for volume; 21 CFR 101.9: nutrition labeling household measures

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