Convert US Gallons to Quarts

About converting US Gallons to Quarts

US Gallons (gal (US)) and Quarts (qt) are both units of volume, so converting between them is a single multiplication: multiply your US Gallons figure by 4. Ten US Gallons comes to 40 Quarts, and a hundred works out at 400 Quarts.

Rule of thumb: going from US Gallons to Quarts multiplies, so the figure always grows — one US Gallon is already 4 Quarts. If your answer came out smaller, you have the conversion the wrong way round.

What is an US Gallon?

The US gallon is defined as exactly 231 cubic inches, a figure inherited unchanged from the old English wine gallon. When Britain overhauled its measures in 1824 and adopted a new imperial gallon, the United States simply kept the wine gallon it already had — and that single decision is the root of the entire US-versus-imperial mess that still catches people out today. The US gallon is roughly a fifth smaller than the imperial one, which means American and British fuel-economy figures are not comparable even though both are quoted in miles per gallon.

What is a Quart?

A quart is a quarter of a gallon, which is exactly where the name comes from — the Latin for a fourth part. Because the American and imperial gallons are different sizes, so are their quarts: the imperial quart is the larger by roughly a fifth, a discrepancy that quietly ruins recipes and technical specs copied across the Atlantic without checking. In the United States the quart is a supermarket fixture — milk, cream, motor oil and paint are all sold in them. Britain, having gone metric on the shelf, has largely dropped it and kept only the pint.

To put both in perspective: a typical American milk jug holds one US gallon, while a quart is the size of a standard carton of American milk.

The converter above updates as you type, and the table lists common values for quick reference. Need the opposite direction? Use the Quarts to US Gallons converter, or browse all Volume converters.