Convert cups to ounces
One US customary cup equals exactly 8 US fluid ounces and exactly 236.5882365 millilitres. Example: 1 cup = 8 fl oz; 2 cups × 8 = 16 fl oz. These are fluid ounces (volume) — the weight of a cup depends on the ingredient (a cup of water weighs about 8.345 oz).
Type a value and get the result with its full working shown — the coefficient, the multiplication and the rounding you choose.
cup (US customary) → fluid ounce (US)
1 × 8 = 8 fl oz
See the exact formula: 1 cup × 8 → fl oz · Source: NIST Handbook 44 / NIST SP 811.
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cups to ounces conversion table
| cup | fl oz |
|---|---|
| 1 cup | 8.0000 fl oz |
| 2 cup | 16.0000 fl oz |
| 3 cup | 24.0000 fl oz |
| 4 cup | 32.0000 fl oz |
| 5 cup | 40.0000 fl oz |
| 6 cup | 48.0000 fl oz |
| 7 cup | 56.0000 fl oz |
| cup | fl oz |
|---|---|
| 8 cup | 64.0000 fl oz |
| 9 cup | 72.0000 fl oz |
| 10 cup | 80.0000 fl oz |
| 25 cup | 200.0000 fl oz |
| 50 cup | 400.0000 fl oz |
| 100 cup | 800.0000 fl oz |
Rounded to 4 decimals · exact values in the calculator above.
The exact formula
The US fluid ounce is 1/128 of a US gallon = exactly 29.5735295625 mL. In cooking it measures liquid volume only. Multiply by 8 (cup → fl oz); reverse: multiply by 0.125.
Unit definitions
- cup (US customary) (cup)
- The US customary cup is exactly 236.5882365 mL, defined as half a US pint. Be aware that the metric cup (250 mL) used in Australia and the older Japanese cup (200 mL) differ. Source: NIST Handbook 44 / NIST SP 811.
- fluid ounce (US) (fl oz)
- The US fluid ounce is 1/128 of a US gallon = exactly 29.5735295625 mL. In cooking it measures liquid volume only. Source: NIST Handbook 44 / NIST SP 811.
Cup to grams by ingredient and method
A cup measures volume, so the gram weight depends on the ingredient, how the cup is filled, and even humidity. For 1 cup of all-purpose flour, published references span 116 to 150 g across six common calibers — spoon-and-level (spoon flour in, then level) gives the low end; dip-and-sweep gives the high end. Values below are typical published references (King Arthur Baking, USDA), not exact definitions.
| Ingredient | Method | 1 cup (g) | 1 tbsp (g) | 1 tsp (g) |
|---|---|---|---|---|
| All-purpose flour | spoon & level | 120 | 7.5 | 2.5 |
| All-purpose flour | dip & sweep (scooped) | 150 | 9.4 | 3.1 |
| Granulated sugar | spoon & level | 200 | 12.5 | 4.2 |
| Granulated sugar | dip & sweep (scooped) | 210 | 13.1 | 4.4 |
| Butter | standard pack (2 sticks) | 227 | 14.2 | 4.7 |
| Rolled oats | spoon & level | 90 | 5.6 | 1.9 |
| Rolled oats | dip & sweep (scooped) | 100 | 6.3 | 2.1 |
| White rice (dry, long grain) | dip & sweep | 185 | 11.6 | 3.9 |
| Water | any method | 237 | 14.8 | 4.9 |
| Honey | poured | 340 | 21.3 | 7.1 |
| Vegetable oil | poured | 218 | 13.6 | 4.5 |
Frequently asked questions
How many ounces in a cup?
A US cup holds exactly 8 US fluid ounces (236.5882365 mL). So 2 cups = 16 fl oz, 4 cups = 32 fl oz.
How many cups is 16 oz?
16 fl oz = 2 cups. Divide fluid ounces by 8: 16 ÷ 8 = 2 cups exactly.
How many grams is a cup of flour?
There is no single authority value — published references for 1 cup of all-purpose flour range from 116 to 150 g, which is exactly why recipes disagree. Spooned-and-leveled flour is about 120 g per cup; scooped (dip the cup into the bin and sweep level) packs up to 150 g, and humidity adds more. Use the ingredient table above — and a kitchen scale when you can.
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