Fluid Ounces to Cups Converter
8 US fluid ounces = 1 US customary cup.
Conversion result
US cups = US fluid ounces ÷ 8; US fluid ounces = cups × 8.
Primary source: NIST SP 811, Appendix B.8 conversion factors. Published SI table values may be rounded; this converter uses the exact underlying definitions. NIST Handbook 44, Appendix C supplies the underlying inch, pound and US liquid measure definitions. NIST SP 1038, footnote 19 defines the US cup, tablespoon and teaspoon in fluid ounces.
Worked example: 12 US fluid ounces ÷ 8 = 1.5 US customary cups.
Common conversion values
The table follows the selected direction. Results display up to 12 significant digits; exact definitions are used before display rounding.
| US fluid ounces | US customary cups |
|---|---|
| 1 | 0.125 |
| 2 | 0.250 |
| 4 | 0.500 |
| 8 | 1.000 |
| 16 | 2.000 |
A US customary cup contains 8 US fluid ounces, each one 128th of a US liquid gallon. This page interprets “oz” as US fluid volume. It cannot turn an ingredient’s mass ounces into cups without density.
Conversions use the measure named on the label. A US customary cup is 236.5882365 mL, rather than a 240 mL nutrition-label cup or a 250 mL metric cup. Actual measuring vessels and ingredient packing may vary.
How to use this tool
Enter a quantity in US fluid ounces, choose the forward or reverse direction, and select Convert. Decimals, fractions such as 1/2, and mixed fractions such as 1 1/2 are supported.
Frequently asked questions
Can I convert 8 ounces of flour to a cup?
Not with a volume-only converter. Mass ounces and fluid ounces are different dimensions. Converting an ingredient’s mass to cups requires its density and preparation method.
Can I reverse the conversion or enter a fraction?
Yes. Choose the reverse direction on this same page. Enter a nonnegative decimal, fraction such as 3/4, or mixed fraction such as 1 1/2. Zero is accepted; the quantity and fraction components are limited to 10¹², and a denominator must be positive.
Is this converter free and private?
Yes. Conversions run on your device without uploading your entries or saving them to browser storage. There is no sign-up.