Convert Imperial fluid ounces to US fluid ounces
1 imperial fluid ounce is 0.96 fl oz. One imperial fluid ounce is exactly 0.960759940404 US fluid ounces.
One imperial fluid ounce is 0.96075994 US fluid ounces. To convert imperial fluid ounces to US fluid ounces, multiply by 0.96075994; to go the other way, divide by 0.96075994 or multiply by 1.0408427. The relation is exact but the figure is not: it is a rounding of a number that does not terminate, and it follows from NIST Handbook 130. One 160th of an imperial gallon, 28.4130625 ml exactly.
Factor checked against the defining standard · How we check
- Imperial fluid ounces × 0.96075994
1 * 0.96075990.961 fl oz
1 imperial fluid ounce in every volume unit
| Unit | Value | Exact factor |
|---|---|---|
| US teaspoons | 5.764559642 tsp | × 5.76455964242 |
| US tablespoons | 1.921519881 tbsp | × 1.92151988081 |
| US fluid ounces | 0.9607599404 fl oz | × 0.960759940404 |
| US cups | 0.1200949926 cup | × 0.12009499255 |
| US pints | 0.06004749628 pt | × 0.0600474962752 |
| US quarts | 0.03002374814 qt | × 0.0300237481376 |
| US gallons | 0.007505937034 gal | × 0.00750593703441 |
| milliliters | 28.4130625 ml | × 28.4130625 |
| liters | 0.0284130625 L | × 0.0284130625 |
| imperial gallons | 0.00625 gal (UK) | × 0.00625 |
| imperial quarts | 0.025 qt (UK) | × 0.025 |
| imperial pints | 0.05 pt (UK) | × 0.05 |
| imperial fluid ounces (as entered) | 1 fl oz (UK) | — |
| imperial gills | 0.2 gi (UK) | × 0.2 |
| cubic millimetres | 28,413.0625 mm³ | × 28,413.0625 |
| cubic centimetres | 28.4130625 cm³ | × 28.4130625 |
| cubic inches | 1.733871455 in³ | × 1.73387145495 |
| cubic feet | 0.001003397833 ft³ | × 0.00100339783272 |
| cubic yards | 0.00003716288269 yd³ | × 0.0000371628826935 |
| cubic metres | 0.0000284130625 m³ | × 0.0000284130625 |
Factors are entered by hand from NIST Handbook 130 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert imperial fluid ounces to US fluid ounces? The converter and the working
- 1.Take the measurement in imperial fluid ounces.
- 2.Multiply by 0.96075994 — that is how many US fluid ounces fit in one imperial fluid ounce.
- 3.To go back the other way, divide by 0.96075994, or multiply by 1.0408427.
Worked example: 25 imperial fluid ounces to US fluid ounces
- Formula
- fl oz (UK) × 0.96075994 = fl oz
- Arithmetic
- 25 × 0.96075994 = 24.02 fl oz
- Answer
- 25 fl oz (UK) = 24.02 fl oz
The factor is rounded for display; the figure above is computed from the full value.
Imperial fluid ounces to US fluid ounces conversion table
| Imperial fluid ounces | US fluid ounces |
|---|---|
| 1 fl oz (UK) | 0.96 fl oz |
| 2 fl oz (UK) | 1.92 fl oz |
| 3 fl oz (UK) | 2.88 fl oz |
| 4 fl oz (UK) | 3.84 fl oz |
| 5 fl oz (UK) | 4.8 fl oz |
| 6 fl oz (UK) | 5.76 fl oz |
| 7 fl oz (UK) | 6.73 fl oz |
| 8 fl oz (UK) | 7.69 fl oz |
| 9 fl oz (UK) | 8.65 fl oz |
| 10 fl oz (UK) | 9.61 fl oz |
| 12 fl oz (UK) | 11.53 fl oz |
| 15 fl oz (UK) | 14.41 fl oz |
| 20 fl oz (UK) | 19.22 fl oz |
| 25 fl oz (UK) | 24.02 fl oz |
| 50 fl oz (UK) | 48.04 fl oz |
| 100 fl oz (UK) | 96.08 fl oz |
| 200 fl oz (UK) | 192.15 fl oz |
| 300 fl oz (UK) | 288.23 fl oz |
| 500 fl oz (UK) | 480.38 fl oz |
| 1000 fl oz (UK) | 960.76 fl oz |
| 2000 fl oz (UK) | 1,921.52 fl oz |
| 5000 fl oz (UK) | 4,803.8 fl oz |
| 10000 fl oz (UK) | 9,607.6 fl oz |
The imperial fluid ounce is the smaller one, against the run of play
The imperial gallon is larger than the US gallon, but the imperial fluid ounce is smaller: 28.4130625 ml against 29.5735295625. The imperial gallon divides into 160 fluid ounces and the US gallon into 128, and dividing a fifth more liquid into a quarter more parts leaves each part about 4% smaller. So a UK recipe asking for 10 fl oz means 284 ml and a US one means 296 ml.
NIST Handbook 44, Appendix C — general tables of units of measurement
What is an imperial fluid ounce?
One 160th of an imperial gallon, 28.4130625 ml exactly. The US fluid ounce is one 128th of a smaller gallon at 29.57 ml, so the two ounces differ by about 4% in the opposite direction to the gallons.
What is a US fluid ounce?
Exactly one 128th of a US gallon, which makes it 29.5735295625 ml exactly. The imperial fluid ounce is a different unit at exactly 28.4130625 ml, so a UK recipe calling for 10 fl oz means 284 ml and a US one means 296 ml. It is also a volume, not a weight: an ounce of flour is not a fluid ounce of flour.
How many US fluid ounces are in an imperial fluid ounce?
One imperial fluid ounce is 0.96075994 US fluid ounces. Going the other way, one US fluid ounce is 1.0408427 imperial fluid ounces. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every volume unit here
The whole group — 20 units with their symbols and the size of each one in liters — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to an imperial fluid ounce.
Cite this page
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- Chicago
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Questions people actually ask
- How many US fluid ounces are in an imperial fluid ounce?
- 0.96075994. Exactly one 128th of a US gallon, which makes it 29.5735295625 ml exactly. The imperial fluid ounce is a different unit at exactly 28.4130625 ml, so a UK recipe calling for 10 fl oz means 284 ml and a US one means 296 ml. It is also a volume, not a weight: an ounce of flour is not a fluid ounce of flour.
- How do I convert US fluid ounces back to imperial fluid ounces?
- Divide by 0.96075994, or multiply by 1.0408427 — they are the same operation.
Other volume conversions
US fluid ounces to imperial fluid ounces — the same conversion the other way.