Cups vs Fluid Ounces
Compare cups and fluid ounces side by side, convert in both directions, and see the exact factor - Volume units.
= 8 fl oz
= 0.125 cup
1 cup = 8 fl oz · 1 fluid ounce = 0.125 cup
The Fluid Ounces is the smaller unit - the same amount has a bigger number when measured in it.
| Cups (cup) | Fluid Ounces (fl oz) | Fluid Ounces (fl oz) | Cups (cup) |
|---|---|---|---|
| 1 | 8 | 1 | 0.125 |
| 2 | 16 | 2 | 0.25 |
| 5 | 40 | 5 | 0.624999 |
| 10 | 80.0001 | 10 | 1.25 |
| 25 | 200 | 25 | 3.125 |
| 50 | 400 | 50 | 6.25 |
| 100 | 800 | 100 | 12.5 |
| 250 | 2,000 | 250 | 31.25 |
| 500 | 4,000 | 500 | 62.4999 |
| 1000 | 8,000 | 1000 | 125 |
Quick Answer
1 cup (cup) = 8 fluid ounces (fl oz), and 1 fluid ounce = 0.125 cups. Cups is the larger unit, so the same physical amount needs a bigger number when measured in Fluid Ounces. Convert either way with the live tool below or the dedicated converter pages.
Key Facts
- 1 cup (cup) = 8 fl oz
- 1 fluid ounce (fl oz) = 0.125 cup
- Conversion is exact multiplication - no rounding in the factor
- Table below covers common values in both directions
- Dedicated converters: cup→fl oz and fl oz→cup pages with live tools
Frequently Asked Questions
Which is bigger, a cup or a fluid ounce?
One cup equals 8 fl oz, and one fluid ounce equals 0.125 cup. The unit with the larger factor is the physically bigger one.
How do I convert cups to fluid ounces?
Multiply by the factor: value in fl oz = value in cup × 8. Example: 5 cup = 40 fl oz. Reverse: divide by 8 (or multiply by 0.125).
Why are cups and fluid ounces different?
They are two different units measuring the same physical quantity. A cup is defined as exactly 8 fl oz, and a fluid ounce as exactly 0.125 cup. Because the units differ in size, the number you write down for the same amount depends on which unit you use - the conversion factor itself is exact, with no rounding.
Is there a quick way to convert without a calculator?
Memorize the 1-to factor: 1 cup ≈ 8 fl oz. Then multiply. For 2 cup that's ≈ 16 fl oz.
Frequently Asked Questions
One cup equals 8 fl oz, and one fluid ounce equals 0.125 cup. The unit with the larger factor is the physically bigger one.
Multiply by the factor: value in fl oz = value in cup × 8. Example: 5 cup = 40 fl oz. Reverse: divide by 8 (or multiply by 0.125).
They are two different units measuring the same physical quantity. A cup is defined as exactly 8 fl oz, and a fluid ounce as exactly 0.125 cup. Because the units differ in size, the number you write down for the same amount depends on which unit you use - the conversion factor itself is exact, with no rounding.
Memorize the 1-to factor: 1 cup ≈ 8 fl oz. Then multiply. For 2 cup that's ≈ 16 fl oz.