How to convert cups to fluid ounces
To convert cups to fluid ounces, multiply by 8. Volume conversions help with recipes, fuel, beverages, aquariums and laboratory work. US customary units are used here.
Cup to Fluid Ounce conversion table
| Cup (cup) | Fluid Ounce (fl oz) |
|---|---|
| 0.1 cup | 0.8 fl oz |
| 0.5 cup | 4 fl oz |
| 1 cup | 8 fl oz |
| 2 cup | 16 fl oz |
| 3 cup | 24 fl oz |
| 4 cup | 32 fl oz |
| 5 cup | 40 fl oz |
| 10 cup | 80 fl oz |
| 20 cup | 160 fl oz |
| 25 cup | 200 fl oz |
| 50 cup | 400 fl oz |
| 100 cup | 800 fl oz |
| 500 cup | 4,000 fl oz |
| 1,000 cup | 8,000 fl oz |
About the units
Cup (cup)
A US customary cup is 8 US fluid ounces, about 236.59 mL (nutrition labels round to 240 mL).
Fluid Ounce (fl oz)
A US fluid ounce is 1/128 of a US gallon, exactly 29.5735295625 mL.
How to use this converter
- Type the number of cups (cup) in the input box.
- The result in fluid ounces appears instantly — no button needed.
- See the same value in every other volume unit just below.
- Use “Swap units” to convert fluid ounces back to cups.
Tips for better results
- Double-check which system a unit belongs to (for example US vs UK gallons).
- Use the swap button to convert in the opposite direction instantly.
- Bookmark the conversions you use most — each pair has its own page.
Frequently asked questions
How many fluid ounces are in one cup?
One cup equals 8 fluid ounces. 8 is the exact factor used by this converter.
How do I convert cups to fluid ounces?
Multiply the value in cups by 8. To go the other way, multiply fluid ounces by 0.125.
What is 10 cup in fl oz?
10 cup = 80 fl oz. Also, 5 cup = 40 fl oz and 100 cup = 800 fl oz.
What is the difference between a cup and a fluid ounce?
A US customary cup is 8 US fluid ounces, about 236.59 mL (nutrition labels round to 240 mL). A US fluid ounce is 1/128 of a US gallon, exactly 29.5735295625 mL.
Is this tool free and private?
Yes — the Cup to Fluid Ounce is completely free with no sign-up, and it runs entirely in your browser, so the values you enter are never uploaded to our servers.
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