How Many Ounces Are in a Cup?
There are 8 fluid ounces in 1 US cup. But note: fluid ounces measure volume — a cup of flour weighs about 4.2 ounces on a scale even though it fills 8 fluid ounces of space.
Cups to fluid ounces
| 1/4 cup | 2 fl oz |
|---|---|
| 1/2 cup | 4 fl oz |
| 3/4 cup | 6 fl oz |
| 1 cup | 8 fl oz |
| 2 cups (1 pint) | 16 fl oz |
| 4 cups (1 quart) | 32 fl oz |
Good to know
This is the most misused conversion in cooking. "8 ounces = 1 cup" is only true for volume (fluid ounces) — for weight it is only true of water and similar liquids. 8 oz of shredded cheese by weight is about 2 cups by volume.
If a recipe lists ounces for a solid ingredient (pasta, cheese, chocolate), it almost always means weight — use a kitchen scale, not a measuring cup.
Frequently asked questions
Is 8 oz always 1 cup?
Only for liquids measured in fluid ounces. For solid ingredients, 8 oz refers to weight and the cup equivalent depends on the ingredient.
How many dry ounces are in a cup?
It depends on the ingredient: a cup of all-purpose flour weighs about 4.2 oz, a cup of granulated sugar about 7 oz, and a cup of water exactly 8.3 oz.
How many ounces is half a cup?
Half a US cup is 4 fluid ounces.
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