How to convert fluid ounces to cups
To convert fluid ounces to cups, multiply by 0.125. Converting fluid ounces to cups helps with recipes, drink sizes and baby bottles, since a US cup holds exactly 8 US fluid ounces.
Fluid Ounce to Cup conversion table
| Fluid Ounce (fl oz) | Cup (cup) |
|---|---|
| 0.1 fl oz | 0.0125 cup |
| 0.5 fl oz | 0.0625 cup |
| 1 fl oz | 0.125 cup |
| 2 fl oz | 0.25 cup |
| 3 fl oz | 0.375 cup |
| 4 fl oz | 0.5 cup |
| 5 fl oz | 0.625 cup |
| 10 fl oz | 1.25 cup |
| 20 fl oz | 2.5 cup |
| 25 fl oz | 3.125 cup |
| 50 fl oz | 6.25 cup |
| 100 fl oz | 12.5 cup |
| 500 fl oz | 62.5 cup |
| 1,000 fl oz | 125 cup |
About the units
Fluid Ounce (fl oz)
A US fluid ounce is 1/128 of a US gallon, exactly 29.5735295625 mL.
Cup (cup)
A US customary cup is 8 US fluid ounces, about 236.59 mL (nutrition labels round to 240 mL).
How to use this converter
- Type the number of fluid ounces (fl oz) in the input box.
- The result in cups appears instantly — no button needed.
- See the same value in every other volume unit just below.
- Use “Swap units” to convert cups back to fluid ounces.
When you’ll use the fluid ounce to cup conversion
A recipe calls for 12 fl oz of milk and your measuring set only has cups. Converting gives exactly 1½ cups.
Your reusable water bottle holds 20 fl oz and you track water intake in cups. Converting shows each bottle counts as 2½ cups.
💡 For a quick estimate in your head, multiply by about 0.13 (the exact factor is 0.125).
Watch out for these mix-ups
- Measuring a weight in ounces with a liquid measuring cup.
- Using British fluid ounces with a US recipe.
- Rounding small amounts in baking.
- Measuring liquids in dry measuring cups that are hard to fill level.
Tips for better results
- Divide fluid ounces by 8 to get US cups.
- Use a clear liquid measuring cup read at eye level.
- Check whether a recipe is American or British.
💡 Practical tip: UK fluid ounces are slightly smaller than US fluid ounces.
Frequently asked questions
How many cups are in one fluid ounce?
One fluid ounce equals 0.125 cups. 0.125 is the exact factor used by this converter.
How do I convert fluid ounces to cups?
Multiply the value in fluid ounces by 0.125. To go the other way, multiply cups by 8.
What is 10 fl oz in cup?
10 fl oz = 1.25 cup. Also, 5 fl oz = 0.625 cup and 100 fl oz = 12.5 cup.
What is the difference between a fluid ounce and a cup?
A US fluid ounce is 1/128 of a US gallon, exactly 29.5735295625 mL. A US customary cup is 8 US fluid ounces, about 236.59 mL (nutrition labels round to 240 mL).
Is this tool free and private?
Yes — the Fluid Ounce to Cup 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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