Cups to Milliliters

The word cup hides at least four sizes. The US customary cup is 236.6 mL. Australia, New Zealand and Canada use a metric cup of 250 mL, about 5.7% larger. A Japanese cup is 200 mL, and the Japanese rice-cooker cup, the traditional gō, is only about 180 mL. US nutrition labels use yet another figure, a legal cup of 240 mL, so a serving of one cup on a cereal box is 240 mL, not 236.6.

For most cooking the gap between 236.6 mL and 250 mL is within what a recipe tolerates. In baking, three or four cups of liquid measured with the wrong cup can shift a batter noticeably, so it is worth knowing where a recipe comes from.

US recipes lean on fractions, and these are the values to keep near the stove: 1/4 cup is 59 mL, 1/3 cup is 79 mL, 1/2 cup is 118 mL, 2/3 cup is 158 mL and 3/4 cup is 177 mL. One cup is 16 tablespoons or 48 teaspoons, and two cups make a US pint of 473 mL.

Dry and liquid measuring cups hold the same volume; the difference is the shape. A liquid cup has a spout and a line below the rim, a dry cup is filled to the brim and leveled with a knife.

Converting cups to milliliters works for liquids. For flour, sugar or cocoa, a volume figure is only as good as the way you filled the cup: a cup of all-purpose flour weighs anywhere from about 120 g spooned and leveled to 150 g scooped and packed. Many bakers switch to grams for that reason, using the recipe author's stated weight if one is given.

To turn a metric measurement back into US cups, use milliliters to cups. Spoon measures are on tablespoons to milliliters.