US Tablespoons to Imperial Gallons (tbsp to gal (UK))

1 US tablespoon equals 0.003252633534 imperial gallons (rounded).

1 US tablespoon = 0.003252633534 imperial gallons

How to convert US tablespoons to imperial gallons

To convert US tablespoons to imperial gallons, multiply the number of US tablespoons by 0.003252633534. The factor is rounded to 10 significant digits. To go the other way, multiply imperial gallons by 307.4431809 (rounded).

imperial gallons = US tablespoons × 0.003252633534

Example: 10 US tablespoons = 0.03252633534 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

US Tablespoon (tbsp)

US customaryCurrent unit

Half a US fluid ounce (14.787 mL), equal to 3 teaspoons.

A tablespoon was once a spoon first and a unit second. Tablespoons entered place settings around 1700, first reserved for soup, and in the 18th century apothecaries used an unofficial tablespoon of four fluid drams, or half a fluid ounce. That is the origin of the modern US definition, which turns the spoon into precisely half a US fluid ounce.

The US tablespoon is therefore 14.7868 milliliters, equal to three US teaspoons, and sixteen of them make a US customary cup. It is often treated as 15 mL, and American nutrition labels define a tablespoon as exactly 15 mL, so the two figures sit within about 1.4 percent of each other. The regional difference that matters is Australia, which uses a larger 20 milliliter tablespoon, so a recipe asking for a tablespoon of oil or baking powder can go wrong when translated across the Pacific.

1 US tablespoon = 0.01478676478 liters (approximately).

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

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

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