How many mL is a cup?

It depends on the recipe's country. A US customary cup is 236.59 mL. A metric cup, used in Australia, New Zealand and Canada, is 250 mL. US nutrition labels use 240 mL under 21 CFR 101.9. The old British imperial cup is 284.13 mL, and a Japanese cup is 200 mL.

Is an Australian cup the same as an American cup?

No. An Australian metric cup is 250 mL and a US customary cup is 236.59 mL, so the Australian cup is 5.7% larger. Australian measuring equipment is defined by AS 1325.

Is 1 cup always 16 tablespoons?

No, and this is where the mistake usually happens. It is true in the United States, where a 236.59 mL cup holds 16 tablespoons of 14.79 mL. In Australia a 250 mL cup holds 12.5 tablespoons, because the Australian tablespoon is 20 mL. Counting out 16 Australian tablespoons gives you 28% more than a cup.

Why is the Australian tablespoon 20 mL?

Australia set its tablespoon at 20 mL when it metricated, giving a clean four to one ratio with the 5 mL teaspoon. Almost everywhere else settled on 15 mL. Australia is the only country using 20 mL, which is why recipes written there do not transfer directly.

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A cup is five different volumes. Nobody tells you which one.

Depending on who wrote your recipe, one cup is 200, 236.59, 240, 250 or 284.13 mL. The largest is 42% bigger than the smallest. Most converters pick one of those, show you a number to five decimal places, and never mention that they chose.

Written and maintained by a Fellow of CPA Australia and CIMA (UK), with 15 years in financial modelling and valuation across banking, financial analytics, utilities and manufacturing. Every figure here is checked against a primary source before it ships.

Published 17 August 2026

Copper measuring cups stamped 1 cup 250 mL and quarter cup 60 mL, the metric sizes used in Australia, New Zealand and Canada. — Look at the stamp. This set says 250 mL to the cup, which is the metric standard. An American set says 240, and neither mentions the other exists.

Key takeaways

Five cup standards are in current use, from 200 mL in Japan to 284.13 mL under old British imperial.
The Australian cup is 5.7% bigger than the American one. Enough to matter in baking, small enough that nothing looks wrong until it comes out of the oven.
Australia is the only country with a 20 mL tablespoon. Everywhere else uses 15.
"1 cup = 16 tablespoons" is false in Australia. A metric cup holds 12.5 Australian tablespoons, so following the American rule leaves you 28% over.
The teaspoon is the one thing everyone agrees on. 5 mL, near enough, worldwide.

The five cups, and who defines each one

The word cup is not one unit. It is five, each written into a different instrument, and all five are in use today.

Standard	Volume	Where it applies
Japanese cup	200 mL	Japan
US customary	236.59 mL	American recipes
US nutrition labelling	240 mL	21 CFR 101.9
Metric cup	250 mL	Australia, New Zealand, Canada
Imperial cup	284.13 mL	Older British recipes

The US customary cup is one sixteenth of a US gallon, which is 231 cubic inches exactly. The imperial cup is half an imperial pint of 568.26125 mL. The metric cup is defined in the Australian standard AS 1325.

Imperial, 284.13 mL

284

Metric, 250 mL

250

US label, 240 mL

240

US customary, 236.59 mL

237

Japanese, 200 mL

200

Bars scaled against a 300 mL axis.

Two of those five sit within four millilitres of each other, which is why almost nobody notices the problem exists. The US customary cup and the labelling cup differ by 1.4%, and no cake has ever failed because of that.

The gap that bites is between American and metric. A US cup is 236.59 mL and a metric cup is 250. That is 5.7%, and it compounds. A recipe using four cups of flour lands you 54 mL out, which is most of a quarter cup.

A measuring spoon stamped 1 tsp 5 ml on one end and 1 Tbsp 15 ml on the other, the sizes used everywhere except Australia. — Fifteen millilitres to the tablespoon, stamped into the metal. Buy the same spoon in Australia and it holds 20.

Australia's tablespoon is the real trap

The cup varies by a few percent. The tablespoon varies by a third.

Almost every country uses a 15 mL tablespoon. The American one is 14.79 mL, which is half a US fluid ounce, and the difference from 15 is too small to measure with a spoon. Australia went to 20 mL when it metricated, giving a tidy four to one ratio against the 5 mL teaspoon.

Australia is alone in that. Not one other country followed, and the spoons look identical in the drawer.

Where it goes wrong. Every American recipe site repeats that 1 cup equals 16 tablespoons. In the United States that is exact: 236.59 divided by 14.79 is 16. In Australia a 250 mL cup holds 12.5 tablespoons, because each one is 20 mL. Count out 16 Australian tablespoons and you have measured 320 mL, which is 28% more than a cup. That is the difference between a cake and a doorstop.

The teaspoon, oddly, is the one place the world agrees. Five millilitres in Australia, the United Kingdom and on American nutrition labels. The US customary teaspoon is 4.93 mL, and nobody has ever noticed the difference outside a laboratory.

What to do about it

Work out where the recipe came from. A .com food blog is almost certainly American, so use 236.59 mL. An Australian, New Zealand or Canadian source means 250. A British cookbook from before the 1970s may well mean 284.

Never convert a cup count into a tablespoon count across countries. That is the step where the 28% error enters, and it enters silently.

For baking, weigh it. This is the real answer and every serious baker gives it. A gram is a gram in every kitchen on earth, and it removes the whole problem in one move.

It also removes a second problem nobody mentions. A cup of flour is not a fixed weight. Scoop it straight from the bag and you compact it. Spoon it in and level it off and you get noticeably less. The measuring standard is only half the variation in a cup of flour.

A vintage balance scale with a dial marked in grammes, the measurement that means the same thing in every country. — A gram is a gram everywhere. It is the only kitchen measurement with no national variant, which is why bakers reach for it.

Common questions

How many mL is a cup?: Between 200 and 284.13, depending on the recipe's origin. The two you will meet most often are 236.59 mL in the United States and 250 mL in Australia, New Zealand and Canada.
Is an Australian cup the same as an American cup?: No. The Australian metric cup is 250 mL against the American 236.59, so it is 5.7% larger.
Is 1 cup always 16 tablespoons?: Only in the United States. In Australia a cup is 12.5 tablespoons, because the Australian tablespoon is 20 mL rather than 15.
Does the teaspoon change too?: Not meaningfully. It is 5 mL almost everywhere, and the US customary 4.93 mL is close enough that no recipe depends on it.

Mojo takeaway

The cup is not a unit, it is five units wearing the same name, and the tablespoon is worse because Australia stands alone at 20 mL. Nothing in your kitchen will tell you which one a recipe meant. Work out where it was written, and for anything that has to rise, put it on a scale instead.

Convert between every cup and spoon standard

Related: grams to cups gives the weight per ingredient rather than one flat number, since a cup of flour and a cup of honey are nowhere near the same. There is also cups to mL with a selector for the standard you actually mean, and the oven temperature and gas mark chart for the other half of an imported recipe.