How many millilitres are in a cup?

236.6 for a US cup and 250 for a metric one. That six percent difference is enough to matter in baking, which is part of why weight-based recipes are more reliable than volume-based ones.

Why is a US gallon different from an imperial gallon?

They descend from different historical standards. A US gallon is 3.785 litres, based on an old English wine gallon; an imperial gallon is 4.546 litres, defined in 1824. The 20 percent gap catches out anyone comparing fuel economy figures.

How many ounces are in a litre?

About 33.8 US fluid ounces, or 35.2 imperial ones. Fluid ounces differ between the systems as well, which is why the same bottle carries two different numbers.

How do I convert litres to gallons?

Divide by 3.785411784 for US gallons or by 4.54609 for imperial. Which one you want depends entirely on where the other number came from.

Is a pint the same everywhere?

No. A US pint is 473 millilitres and an imperial pint is 568 — nearly 20 percent more, which is why a pint in a British pub is noticeably larger than one in an American bar.

Volume Converter

Convert litres, gallons, cups, pints, spoons and fluid ounces.

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About the Volume Converter

Convert between litres, millilitres, gallons, cups, pints and more in one place. Values update as you type, and the result is calculated by converting to a base unit and back — so the arithmetic is the same in both directions and round-tripping a number returns exactly what you started with.

The trap here is that US and imperial measures share names and differ in size. A US gallon is 3.785 litres and an imperial gallon is 4.546 — a 20 percent difference. A US pint is 473 millilitres, an imperial pint 568. Recipes and fuel figures cross the Atlantic constantly and the units rarely announce which system they mean.

Cups are worse still: a US cup is 236.6 millilitres, a metric cup 250, and an Australian tablespoon is 20 millilitres against 15 everywhere else. For baking, weight is simply more reliable than volume — which is why serious recipes give grams.

How it works

Type a value and choose the units to convert between.
The result updates as you type, with the same value shown in every other unit below.
Jump straight to a direct page for the common conversions listed at the bottom.

Frequently asked questions

How many millilitres are in a cup?: 236.6 for a US cup and 250 for a metric one. That six percent difference is enough to matter in baking, which is part of why weight-based recipes are more reliable than volume-based ones.
Why is a US gallon different from an imperial gallon?: They descend from different historical standards. A US gallon is 3.785 litres, based on an old English wine gallon; an imperial gallon is 4.546 litres, defined in 1824. The 20 percent gap catches out anyone comparing fuel economy figures.
How many ounces are in a litre?: About 33.8 US fluid ounces, or 35.2 imperial ones. Fluid ounces differ between the systems as well, which is why the same bottle carries two different numbers.
How do I convert litres to gallons?: Divide by 3.785411784 for US gallons or by 4.54609 for imperial. Which one you want depends entirely on where the other number came from.
Is a pint the same everywhere?: No. A US pint is 473 millilitres and an imperial pint is 568 — nearly 20 percent more, which is why a pint in a British pub is noticeably larger than one in an American bar.

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