To convert millilitres to cups, divide by the size of the cup your recipe uses: 237 for a US cup, or 250 for a metric cup. So 500 ml is about 2.1 US cups or 2 metric cups. The volume converter does it instantly across US and UK measures.
That is the answer, with one catch worth understanding: a cup is not the same size everywhere.
Why a cup is not one size
Unlike a litre or a millilitre, a cup is a customary measure that varies by country. The common ones are:
- US cup: about 237 ml (formally 236.59 ml).
- Metric cup: exactly 250 ml, used in Australia, New Zealand and much of the metric world.
- UK cup: about 284 ml, an older imperial measure now rarely used; modern UK recipes favour grams and millilitres.
Most recipes you find online are American, so the US cup is the safest default, but it is always worth checking where a recipe comes from before you measure.
How to convert ml to cups
Millilitres to US cups
Divide by 237.
- 240 ml → about 1 cup
- 500 ml → about 2.1 cups
Millilitres to metric cups
Divide by 250.
- 250 ml → 1 cup
- 500 ml → 2 cups
The volume converter handles US and UK gallons, pints, fluid ounces, tablespoons and teaspoons too.
When the difference matters
For a soup or a stew, the gap between a 237 ml and a 250 ml cup will not ruin anything. For baking, it can. Cakes, breads and pastry rely on ratios between flour, liquid and fat, and a five percent error repeated across several ingredients adds up. If a recipe is fussy, the most reliable approach is to weigh ingredients on a kitchen scale rather than measure by cup at all, since weight does not vary the way volume scoops do.
A note on tablespoons and teaspoons
These vary slightly too. A US tablespoon is about 14.8 ml and a teaspoon about 4.9 ml, while a metric tablespoon is 15 ml and a teaspoon 5 ml. Close enough for almost all cooking, but the converter gives the exact figure if you need it.
To convert ingredient weights, see the weight converter.