Volume / US cup → US fl oz
Convert US customary cups to US fluid ounces
Convert liters, milliliters, cubic meters, and clearly labeled US and imperial measures for liquids and capacity. Convert US customary cups (US cup) to US fluid ounces (US fl oz). Find the formula, worked examples, unit definitions, and practical guidance below.
Reverse: US fluid ounces to US customary cups →
How to convert US customary cups to US fluid ounces
US customary, imperial, and metric kitchen measures can have different sizes despite similar names. Use the system printed on your recipe or container.
Use x for the value in US cup, b for the intermediate value in L, and y for the result in US fl oz.
US fl oz = US cup × 0.2365882365 ÷ 0.0295735295625
Worked examples
10 US cup ≈ 80 US fl oz
Step 1: (10 × 0.2365882365) ≈ 2.365882365 L.
Step 2: 2.365882365 ÷ 0.0295735295625 ≈ 80 US fl oz.20 US cup ≈ 160 US fl oz
Step 1: (20 × 0.2365882365) ≈ 4.73176473 L.
Step 2: 4.73176473 ÷ 0.0295735295625 ≈ 160 US fl oz.
Results are rounded to 12 significant digits. Converting units does not increase the precision of the original measurement. Very large or small values outside JavaScript’s finite numeric range are rejected.
About US customary cups
A US customary cup is half a US liquid pint, or exactly 236.5882365 milliliters. This is not a 240 mL nutrition-label cup or a 250 mL metric cup.
About US fluid ounces
A US fluid ounce is one 128th of a US liquid gallon. It measures volume and is different from an imperial fluid ounce or an ounce of mass.
Definitions and sources
Check which gallon, cup, or ounce you mean
A US liquid gallon contains 3.785411784 liters; an imperial gallon contains 4.54609 liters. This calculator labels both explicitly and does not substitute one for the other.
Our US customary cup is 236.5882365 mL. A recipe may instead use a 250 mL metric cup or a 240 mL cup. Fluid ounces measure volume, while ounces in the Weight category measure mass.
For a tank or room, calculate the volume using dimensions in the same length unit before converting its cubic units. Changing only one side’s unit will give an incorrect volume.
Check the cup or fluid-ounce convention before using a converted volume in recipe calculations.
US customary cups to US fluid ounces reference table
| US customary cups (US cup) | US fluid ounces (US fl oz) |
|---|---|
| 1 | 8 |
| 5 | 40 |
| 10 | 80 |
| 25 | 200 |
| 50 | 400 |
| 100 | 800 |
| 1000 | 8000 |
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