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Convert US cups to US fluid ounces

1 US cup is 8 fl oz. One US cup is exactly 8 US fluid ounces.

US fluid ounces
8 fl oz
US cups × 8
value * 88 fl oz

1 US cup in every volume unit

UnitValueExact factor
US teaspoons48 tsp× 48
US tablespoons16 tbsp× 16
US fluid ounces8 fl oz× 8
US cups (as entered)1 cup
US pints0.5 pt× 0.5
US quarts0.25 qt× 0.25
US gallons0.0625 gal× 0.0625
millilitres236.5882365 ml× 236.5882365
litres0.2365882365 L× 0.2365882365

Factors are entered by hand from NIST Handbook 130 rather than derived from a units library, so the ones that terminate are exact rather than rounded.

How to convert

  1. 1.Take the measurement in US cups.
  2. 2.Multiply by 8 — that is how many US fluid ounces fit in one US cup.
  3. 3.To go back the other way, divide by 8, or multiply by 0.125.

US cups to US fluid ounces conversion table

US cupsUS fluid ounces
1 cup8 fl oz
2 cup16 fl oz
3 cup24 fl oz
4 cup32 fl oz
5 cup40 fl oz
6 cup48 fl oz
7 cup56 fl oz
8 cup64 fl oz
9 cup72 fl oz
10 cup80 fl oz
12 cup96 fl oz
15 cup120 fl oz
20 cup160 fl oz
25 cup200 fl oz
50 cup400 fl oz
100 cup800 fl oz

The two units

US cup (cup)
Eight US fluid ounces, about 236.6 ml. The "legal" cup on nutrition labels is a rounded 240 ml.
US fluid ounce (fl oz)
Exactly one 128th of a US gallon, which makes it 29.5735295625 ml exactly. The imperial fluid ounce is a different unit at exactly 28.4130625 ml, so a UK recipe calling for 10 fl oz means 284 ml and a US one means 296 ml. It is also a volume, not a weight: an ounce of flour is not a fluid ounce of flour.

Source: NIST Handbook 130 — US customary liquid measure

Questions people actually ask

How many US fluid ounces are in a US cup?
8. Exactly one 128th of a US gallon, which makes it 29.5735295625 ml exactly. The imperial fluid ounce is a different unit at exactly 28.4130625 ml, so a UK recipe calling for 10 fl oz means 284 ml and a US one means 296 ml. It is also a volume, not a weight: an ounce of flour is not a fluid ounce of flour.
How do I convert US fluid ounces back to US cups?
Divide by 8, or multiply by 0.125 — they are the same operation.

Other volume conversions

US fluid ounces to US cups — the same conversion the other way.

Calculators that work in volume