Cup to Fluid Ounce Converter

How to convert cups to fluid ounces

To convert cups to fluid ounces, multiply by 8. A US cup holds exactly 8 US fluid ounces, but nutrition labels and other countries use slightly different cups, which matters for precise recipes.

Cup to Fluid Ounce conversion table

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

1. Type the number of cups (cup) in the input box.
2. The result in fluid ounces appears instantly — no button needed.
3. See the same value in every other volume unit just below.
4. Use “Swap units” to convert fluid ounces back to cups.

When you’ll use the cup to fluid ounce conversion

A smoothie recipe calls for 1½ cups of juice but your measuring jug is marked in fluid ounces. Converting gives 12 fl oz.

You are tracking drinks and a water bottle holds 24 fl oz. Converting shows it equals 3 cups toward your daily goal.

💡 The factor is exact and easy to remember: 1 cup = 8 fl oz.

Watch out for these mix-ups

• Measuring dry ingredients in fluid ounces, which measure volume, not weight.
• Using a UK or metric cup with a US recipe.
• Thinking the 8 oz on a cup means eight ounces of weight.
• Assuming nutrition-label cups are exactly 8 fl oz.

Tips for better results

• Use liquid measuring cups for liquids and dry cups for dry ingredients.
• Check whether a recipe is American, British or Australian.
• Weigh dry ingredients for accuracy.

💡 Practical tip: Fluid ounces measure volume and ounces measure weight — 8 fl oz of honey weighs far more than 8 oz.

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