Ounces to Cups (fl oz to cups)
A US customary cup is exactly 8 US fluid ounces (236.5882365 ml; the fluid ounce is 1/128 of the 231-cubic-inch gallon, NIST SP 811), so divide fluid ounces by 8. 20 fl oz is 2.5 cups.
Formula
cups = US fl oz ÷ 8
Example: 4 US fluid ounces = 0.5 US cups.
Ounces to Cups chart
| US fluid ounces | US cups |
|---|---|
| 1 | 0.125 |
| 2 | 0.25 |
| 3 | 0.375 |
| 4 | 0.5 |
| 5 | 0.625 |
| 6 | 0.75 |
| 8 | 1 |
| 10 | 1.25 |
| 12 | 1.5 |
| 16 | 2 |
| 20 | 2.5 |
| 24 | 3 |
| 32 | 4 |
| 40 | 5 |
| 48 | 6 |
| 64 | 8 |
| 128 | 16 |
Good to know
Fluid vs dry ounces: this chart is for liquids measured by volume. An ounce on a bag of flour or chocolate chips is weight, and 8 oz by weight of flour is close to 1.9 cups, not 1. For dry ingredients weigh them or use a grams-per-cup table.
Up the scale: 16 fl oz = 2 cups = 1 pint, 32 fl oz = 4 cups = 1 quart, and 128 fl oz = 16 cups = 1 gallon. A 12 oz can of soda is 1.5 cups and a 64 oz jug is 8 cups.
Other cups: US nutrition labels use a 240 ml 'legal' cup (8.12 fl oz) and Australia, Canada and New Zealand use a 250 ml metric cup (8.45 US fl oz). For most recipes the difference is under 6%.
Frequently asked questions
How many ounces are in a cup?
8 US fluid ounces in a US cup.
How many cups is 16 oz?
16 fl oz is 2 cups (1 pint).
How many cups is 12 oz?
12 fl oz is 1.5 cups.
Is 8 oz of flour 1 cup?
No. 8 oz of flour by weight is about 1.9 cups. The 8-ounces-per-cup rule only applies to fluid ounces.