Volume conversion
21 fl oz to cups
2.625 cups
21 US fluid ounces = 2.625 US cups. Exact factor: cups = fl oz ÷ 8.
Live converter
Edit either field — the other updates instantly. Type decimal values like 38.4.
The formula
cups = fl oz ÷ 8
Worked example: 21 × 0.125 = 2.625 cups.
Values near 21 fl oz
| fl oz | cups |
|---|---|
| 18 | 2.25 |
| 19 | 2.375 |
| 20 | 2.5 |
| 21this page | 2.625 |
| 22 | 2.75 |
| 23 | 2.875 |
| 24 | 3 |
Frequently asked
How do you convert US fluid ounces to US cups?
Apply the formula cups = fl oz ÷ 8. Enter any value in the live converter above and the result updates as you type.
What is 21 fl oz in cups?
21 fl oz equals 2.625 cups. The reference table below shows the values immediately around 21 fl oz.
Is this conversion exact?
Yes. If a recipe gives ounces for a dry ingredient it usually means weight, not fluid ounces — check before pouring.