Firkins to US Gallons (firkin to gal)

1 firkin equals 10.80854933 US gallons (rounded).

1 firkin = 10.80854933 US gallons

How to convert firkins to US gallons

To convert firkins to US gallons, multiply the number of firkins by 10.80854933. The factor is rounded to 10 significant digits. To go the other way, multiply US gallons by 0.09251935385 (rounded).

US gallons = firkins × 10.80854933

Example: 10 firkins = 108.0854933 US gallons.

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

Firkin (firkin)

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

9 imperial gallons (40.9 L), a quarter of a barrel. A traditional cask size for beer.

Probably from Middle English ferdekyn, which in turn likely comes from a Middle Dutch diminutive of vierde, fourth, the firkin is literally a little quarter: a quarter of a barrel. For beer in Britain that means 9 imperial gallons, about 41 liters (40.9 L here), or 72 imperial pints.

The word has been used for other goods too. A wine firkin was much bigger, at 70 imperial gallons by one reckoning, while British butter and cheese were sold by the firkin of 56 pounds, about 25 kilograms. An American dry firkin of 9 US gallons is only about 34 liters, and the word could also mean any small wooden tub for butter, lard or fish. Authors such as William Robinson in 1825 treated it as a recognised trade measure.

1 firkin = 40.91481 liters (exactly).

Sources: Wikipedia: Firkin (unit); Wikipedia: Barrel (unit); Wikipedia: Cask ale

US Gallon (gal)

US customaryCurrent unit

Exactly 231 cubic inches or 3.785411784 liters (128 US fluid ounces). About 17% smaller than the imperial gallon.

The US gallon is a survivor of English wine trade. Around 1706, a statute in Queen Anne's reign fixed the wine gallon at exactly 231 cubic inches, settling confusion among the competing gallons for wine, ale and corn. British colonies in North America used that wine gallon, and in 1824 Britain replaced all its gallons with a new imperial one while the United States kept the old measure. It was adopted as the legal US standard in 1836 and is still defined as exactly 231 cubic inches, or 3.785411784 liters.

That makes the US gallon about 17 percent smaller than the imperial gallon, a difference that explains why American and British fuel-economy figures cannot be compared directly. Everyday uses are milk jugs, paint cans and gasoline pumps. One gallon divides evenly into four quarts, eight pints, sixteen cups and 128 fluid ounces. A gallon of water weighs a little over 8 pounds, an easy figure to remember when loading a car with water jugs.

1 US gallon = 3.785411784 liters (exactly).

Sources: Wikipedia: Gallon; NIST SP 811, Appendix B.8: conversion factors for volume

Related conversions

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