US Fluid Ounces to Imperial Gills (fl oz to gi (UK))

1 US fluid ounce equals 0.2081685462 imperial gills (rounded).

1 US fluid ounce = 0.2081685462 imperial gills

How to convert US fluid ounces to imperial gills

To convert US fluid ounces to imperial gills, multiply the number of US fluid ounces by 0.2081685462. The factor is rounded to 10 significant digits. To go the other way, multiply imperial gills by 4.803799702 (rounded).

imperial gills = US fluid ounces × 0.2081685462

Example: 10 US fluid ounces = 2.081685462 imperial gills.

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

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

Imperial Gill (gi (UK))

Imperial (British)Traditional unit (still used in some regions)

Five imperial fluid ounces, 142.07 mL, a quarter of an imperial pint. Formerly a UK spirits measure.

Gill, pronounced with a soft g, is the quarter pint of the imperial system: five imperial fluid ounces, or 142.0653125 milliliters, which is about 4.8 US fluid ounces. Four gills make a pint, eight make a quart and thirty-two make a gallon. The unit is also known as a teacup, and half a gill is sometimes called a jack.

Its best-known use was in selling spirits. Before metrication, English pubs poured spirits in sixths of a gill (about 23.7 mL), Scottish bars in fifths (28.4 mL) or quarters (35.5 mL), and Northern Ireland and the Republic of Ireland used the quarter gill. Scottish drinkers also had names such as the nip for a quarter gill and the wee gill for three quarters of a gill. After UK metrication, pubs moved to 25 mL or 35 mL measures, while the Isle of Man kept the one-fifth gill until 2022. Outside the drinks trade the gill is now rare and mostly appears in old recipes and statutes.

1 imperial gill = 0.1420653125 liters (exactly).

Sources: Wikipedia: Gill (unit); NIST SP 811 Appendix B.8: conversion factors; UK Weights and Measures Act 1985, Schedule 1

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