Convert millilitres to US fluid ounces. Divide by 29.5735, with cooking tables and the difference between US and imperial fluid ounces.

The formula

US fluid ounces = millilitres ÷ 29.5735295625

This is a fluid ounce — a measure of volume. It is not the ounce that weighs 28.35 grams. The two share a name and nothing else; see grams to ounces for the weight one.

US and imperial fluid ounces

They differ by about 4%, and unusually the imperial one is the smaller:

	Millilitres
US fluid ounce	29.5735
Imperial fluid ounce	28.4131

This converter uses the US fluid ounce. The 4% gap is small enough to ignore for a drink and large enough to matter across a recipe scaled up ten times.

Quick reference

Millilitres	US fl oz	Imperial fl oz
1 ml	0.034 oz	0.035 oz
29.57 ml	1 oz	1.041 oz
50 ml	1.69 oz	1.76 oz
100 ml	3.38 oz	3.52 oz
250 ml	8.45 oz	8.80 oz
500 ml	16.91 oz	17.60 oz
1000 ml	33.81 oz	35.20 oz

Cooking

Millilitres	US fl oz	Also
5 ml	0.17 oz	1 teaspoon
15 ml	0.51 oz	1 tablespoon
30 ml	1.01 oz	1 fluid ounce
59 ml	2 oz	¼ US cup
118 ml	4 oz	½ US cup
237 ml	8 oz	1 US cup
473 ml	16 oz	1 US pint

An American recipe that says “8 oz” of a liquid means one cup. If it says “8 oz” of a solid — flour, chocolate, cheese — it means the weight ounce, which is 227 g. The same two characters mean two different things in the same ingredient list, and only the context distinguishes them.

Drinks

	Millilitres	US fl oz
Espresso	30 ml	1.01 oz
Small water bottle	500 ml	16.9 oz
US soda can	355 ml	12 oz
European soda can	330 ml	11.2 oz
Wine bottle	750 ml	25.4 oz
US pint of beer	473 ml	16 oz
UK pint of beer	568 ml	19.2 oz

A UK pint is 20 imperial fluid ounces and a US pint is 16 US fluid ounces, which is why a British pint is noticeably larger despite both being called a pint.

Estimating in your head

Divide by 30. 250 ml ÷ 30 is 8.33 against a true 8.45 US fl oz — about 1.5% low, and easier than any alternative.

Millilitres to fluid ounces