Cubic Feet to Imperial Gallons (ft³ to gal (UK))

1 cubic foot equals 6.228835459 imperial gallons (rounded).

1 cubic foot = 6.228835459 imperial gallons

How to convert cubic feet to imperial gallons

To convert cubic feet to imperial gallons, multiply the number of cubic feet by 6.228835459. The factor is rounded to 10 significant digits. To go the other way, multiply imperial gallons by 0.1605436532 (rounded).

imperial gallons = cubic feet × 6.228835459

Example: 10 cubic feet = 62.28835459 imperial 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

Cubic Foot (ft³)

US & ImperialCurrent unit

Exactly 28.316846592 liters (1,728 cubic inches). Used for refrigerator capacity, gas volume and shipping.

Cubic foot grew from the foot itself, a length unit with ancient origins, cubed into a volume of 1,728 cubic inches. Since the international foot was fixed at exactly 0.3048 meters, it equals exactly 28.316846592 liters. It sits at the center of the Anglo-American cubic system, a cube you could build from twelve-inch rulers, and it is about 7.48 US gallons or 6.23 imperial gallons.

In practice the cubic foot is the language of capacity and flow. Natural gas and household water are often billed per hundred cubic feet, written CCF, while gas reserves are reported in thousands and trillions of cubic feet. Rivers are measured in cubic feet per second, called cusecs, and fans and air compressors are rated in cubic feet per minute. To picture one, imagine a box a foot on each side holding a bit under seven and a half gallon jugs of water.

1 cubic foot = 28.31684659 liters (approximately).

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

Imperial Gallon (gal (UK))

Imperial (British)Current unit

Exactly 4.54609 liters, the volume of 10 pounds of water. Used for fuel economy in the UK (miles per gallon) and historically across the Commonwealth.

Britain unified its confusing gallons by act of Parliament in 1824. Before then, the country used separate ones for wine at 231 cubic inches, ale at 282 and corn at about 268.8. The 1824 reform replaced them with the imperial gallon, defined as the volume of ten pounds of distilled water, calculated at 277.274 cubic inches. A new definition in 1889 slightly changed that, and after the liter was restored to exactly a cubic decimeter in 1964, Canada and then the UK in 1976 adopted the exact value of 4.54609 liters.

Because the United States kept the 231-cubic-inch wine gallon, an imperial gallon is about 20 percent larger than a US gallon. That explains why a car rated at 40 miles per gallon in Britain is less impressive in American terms, since it comes to roughly 33 US miles per gallon. Ireland dropped the gallon as a primary trade unit at the end of 1993 and the UK at the end of September 1995, but it lives on in British fuel-economy figures and older recipes.

1 imperial gallon = 4.54609 liters (exactly).

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

Related conversions

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