How Many ml in a Cup? US, Metric and Imperial Cups

Published October 9, 2026

Three cups, three volumes

The US customary cup is 236.588 ml — 8 US fluid ounces, 16 US tablespoons, 48 teaspoons. The metric cup used in Australia, New Zealand and most modern non-US recipes is exactly 250 ml. The imperial cup of older British cookbooks is 284.131 ml — half an imperial pint, 20 % more than the US cup.

• US cup — 236.588 ml (rounded to 240 ml on American nutrition labels)
• Metric cup — exactly 250 ml
• Imperial cup (UK) — 284.131 ml

Quick conversion: cup fractions in ml

The splits recipes actually call for, in each system — rounded to the tenth.

• US cup: ¼ = 59.1 ml · ⅓ = 78.9 ml · ½ = 118.3 ml · ⅔ = 157.7 ml · ¾ = 177.4 ml
• Metric cup: ¼ = 62.5 ml · ⅓ ≈ 83.3 ml · ½ = 125 ml · ¾ = 187.5 ml
• Imperial cup: ¼ ≈ 71.0 ml · ½ ≈ 142.1 ml · ¾ ≈ 213.1 ml

Which cup does your recipe mean?

American recipes — and American measuring sets — mean the US cup. Recipes from Australia, New Zealand and most metric-world cookbooks mean the 250 ml cup; Canadian recipes switched to metric cups in the 1970s but older ones can still assume imperial. British recipes published before metrication use the imperial cup — recent ones often give grams directly. When in doubt, check the publisher's country and the recipe's other measurements: grams alongside cups usually signal metric.

The difference is not academic: a batter measured in imperial cups takes almost 50 ml more liquid per cup than a US one — the gap between a firm dough and a loose one.

From milliliters to grams is a second step

Milliliters give you the volume; grams depend on what fills it. A US cup of water weighs 237 g (density 1.0 g/ml), the same cup of all-purpose flour only 125 g (0.529 g/ml), of olive oil 217 g (0.916), of honey a heavy 336 g (1.42). That is why « 1 cup in grams » has a different answer per ingredient — our converters apply each ingredient's measured density.

For water-like liquids, ml and grams nearly coincide

Liquids built on water sit within a few points of 1 g/ml: whole milk 1.03 (244 g per US cup), heavy cream 0.99 (234 g), white wine 0.99, stock 1.0. For those, reading milliliters as grams errs by 3–4 % at most — invisible in a soup, acceptable in a sauce. Oils are lighter (~0.92) and syrups much heavier, so the shortcut stops there.

One last shortcut: spoons inside the cup

A US cup is exactly 16 US tablespoons — so « ½ cup plus 2 tbsp » reads as 10 spoons, or 147.9 ml. Metric tablespoons (15 ml) do not divide the metric cup evenly: 250 ml makes 16⅔ spoons, which is why Australian recipes count in quarter cups. When a recipe straddles both systems — a US cup of butter in a metric kitchen — weigh it: our converters carry every ingredient from cups to grams in both directions.