How many fluid ounces are in a US cup?

One US customary cup equals exactly 8 US fluid ounces (fl oz), which is 236.588 ml. This is the standard cup size used in most American recipes and the most widely recognised cup measurement internationally.

Is a cup 8 oz or 16 oz?

A standard US cup is 8 fluid ounces. A 16 fl oz measurement is equal to 2 cups (often called a pint in US measure). Confusion sometimes arises with dry weight ounces: 1 cup of water weighs approximately 8.33 weight ounces, while 1 cup of flour weighs around 4.25 weight ounces because the weight depends on what is being measured.

How many ounces are in a metric cup?

A metric cup, used in Australia, New Zealand, and Canada, equals 250 ml. This is approximately 8.45 US fluid ounces, or 8.80 UK fluid ounces. The metric cup is slightly larger than the US customary cup (236.588 ml) but smaller than the UK imperial cup (284.131 ml / 10 fl oz).

Cups to Ounces (oz) Converter

Convert cups to fluid ounces (fl oz) or to millilitres. Choose between US customary cups (236.588 ml), metric cups used in NZ and Australia (250 ml), or UK imperial cups (284.131 ml). Enter your cup quantity and cup type to see the result instantly.

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Standard conversion US customary: 1 cup = 8 fl oz = 236.588 ml. Metric: 1 cup = 250 ml. UK imperial: 1 cup = 10 fl oz = 284.131 ml.

1. Your Measurement

Number of cups

cups

Cup type

2. Output Units

Fluid ounce type (for fl oz result)

Common fractions (quick presets)

Conversion Result

Fluid Ounces
-
fl oz

Millilitres

Litres

Tablespoons

US tablespoons (14.787 ml)

Common Cups to oz Reference Table

Cups	US fl oz	ml	Litres

Conversion Breakdown

Input-

Cup type-

ml per cup-

Total ml-

fl oz type-

ml per fl oz-

Total fl oz-

Other Equivalents

US teaspoons (4.929 ml)-

US tablespoons (14.787 ml)-

US fl oz (29.5735 ml)-

UK fl oz (28.4131 ml)-

Millilitres-

Litres-

Cubic centimetres (cc)-

How to Convert Cups to Ounces

To convert cups to fluid ounces, multiply the number of cups by the number of fluid ounces in one cup for your cup type:

US customary cup: cups x 8 = US fl oz (1 cup = 8 fl oz = 236.588 ml)
Metric cup (NZ, AU, CA): cups x 250 = ml, then divide by 29.5735 for US fl oz (approx 8.454 US fl oz per metric cup)
UK imperial cup: cups x 10 = UK fl oz (1 cup = 10 UK fl oz = 284.131 ml)

The formula for US cups to US fluid ounces is the simplest: multiply by 8. For other combinations, convert to ml first then divide by the ml per fl oz for the desired output unit.

Cup Sizes Around the World

A "cup" is not a universal measurement. The three most commonly encountered cup sizes are:

Cup Type	Exact Volume (ml)	US fl oz	UK fl oz	Where Used
US customary cup	236.588 ml	8.000	8.327	USA, most international recipes
Metric cup	250.000 ml	8.454	8.799	New Zealand, Australia, Canada
UK imperial cup	284.131 ml	9.608	10.000	Historical UK use

For everyday cooking in New Zealand, the metric cup (250 ml) is standard. If a recipe says "1 cup" without specifying, it usually refers to the US cup (236.588 ml) if from an American source, or the metric cup (250 ml) if from a New Zealand or Australian source. The difference of about 13 ml per cup is usually small enough to ignore in most recipes, but it can matter in baking where precision is important.

Fluid Ounces vs Weight Ounces

Fluid ounces (fl oz) measure volume, while weight ounces (oz) measure mass. These are different units. When converting cups to ounces for a liquid like water, 1 US cup of water is very close to 8.33 weight ounces (because water is approximately 1 g/ml and 1 weight oz is 28.35 g). However, for other ingredients the weight per cup varies significantly:

1 US cup of all-purpose flour: approximately 4.25 weight oz (120 g)
1 US cup of sugar (granulated): approximately 7.05 weight oz (200 g)
1 US cup of butter: approximately 8.00 weight oz (227 g)
1 US cup of rice (uncooked): approximately 6.35 weight oz (180 g)
1 US cup of milk: approximately 8.64 weight oz (245 g)

This converter handles fluid ounces (volume). To convert cups of a specific ingredient to weight ounces, you need to know that ingredient's density.

Worked Example

Convert 2 US cups to US fluid ounces:

1 US cup = 8 US fl oz
2 cups x 8 = 16 US fl oz
In millilitres: 2 x 236.588 = 473.18 ml
In tablespoons: 16 fl oz / 0.5 fl oz per tbsp = 32 US tablespoons

This matches the default output of the converter above (2 US cups = 16 fl oz = 473.18 ml).

Related Calculators

Essential Calculators: all converters and tools in one place.
Grams to Cups Converter: convert ingredient weights to cup measures.
Ounces to Millilitres Converter: convert fl oz to ml directly.
ml to Grams Calculator: convert millilitres to grams by ingredient.
Grams to Ounces Calculator: weight unit conversion for cooking and baking.

Sources and method: US customary cup = 236.588 ml (NIST Handbook 44, 2023 edition). Metric cup = 250 ml (Standards Australia, Standards New Zealand). UK imperial cup = 284.131 ml (10 UK fl oz). US fl oz = 29.5735 ml. UK fl oz = 28.4131 ml. US tablespoon = 14.7868 ml. US teaspoon = 4.9289 ml.

This converter handles fluid volume only. To convert cups of a specific ingredient to weight ounces, the density of that ingredient is required. Results are rounded to four decimal places for display.