This converter turns imperial fluid ounces into US cups instantly, using the exact factor 1 imperial fluid ounce = 0.1200949926 US cups. Type any number and the result updates as you go — nothing is sent to a server, so the arithmetic happens entirely in your browser.
The UK fluid ounce, about 4% smaller than its US counterpart. The US legal cup used in recipes: 240 mL, or 236.6 mL by the customary definition.
Because the relationship is a simple proportion, one multiplication does the whole job. The table further down gives pre-computed values for the amounts people look up most often, and the result panel also reports the reverse conversion so you can check the figure both ways.
The formula
imperial fluid ounces- The amount you are converting, measured in imperial fluid ounces
0.1200949926- The exact number of US cups in one imperial fluid ounce
US cups- The converted result
How it works, step by step
- Enter the number of imperial fluid ounces you want to convert.
- The value is multiplied by 0.1200949926, the exact conversion factor.
- The result is displayed in US cups, rounded for readability.
- The unrounded value and the reverse conversion appear underneath so you can verify it.
Worked examples
Converting 5 imperial fluid ounces
Multiply 5 by 0.12009499. That gives 0.600475 US cups. A quick sanity check: one imperial fluid ounce is smaller than one US cup, so the number should get smaller — and it does.
Converting 72 imperial fluid ounces
72 × 0.12009499 = 8.6468 US cups. Working backwards, 8.6468 ÷ 0.12009499 returns 72 imperial fluid ounces, which confirms the factor is applied the right way round.
How to read your score
Frequently asked questions
How many US cups are in one imperial fluid ounce?
Exactly 0.1200949926. Every conversion on this page is that single number multiplied by your input, so the result carries no rounding error beyond what is shown.
What is the formula to convert imperial fluid ounces to US cups?
Us Cups = imperial fluid ounces × 0.1200949926. To reverse it, divide instead: imperial fluid ounces = US cups ÷ 0.1200949926, which is the same as multiplying by 8.326741846.
Is the imperial fluid ounce bigger than the US cup?
No. One imperial fluid ounce is only 0.120095 of a US cup, so the US cup is the larger unit.
Why does my answer differ slightly from other imperial-fluid-ounces to cups converters?
Most differences come from rounding the factor too early. This tool keeps full double precision through the calculation and only rounds at the final display step, and it also shows the unrounded value so you can see exactly where any difference appears.
What is a imperial fluid ounce?
The UK fluid ounce, about 4% smaller than its US counterpart.
What is a US cup?
The US legal cup used in recipes: 240 mL, or 236.6 mL by the customary definition.
Imperial Fluid Ounces to US cups reference table
| Imperial Fluid Ounces | Us Cups |
|---|---|
| 0.5 fl oz | 0.060047 cup |
| 1 fl oz | 0.120095 cup |
| 2 fl oz | 0.24019 cup |
| 3 fl oz | 0.360285 cup |
| 5 fl oz | 0.600475 cup |
| 10 fl oz | 1.2009 cup |
| 15 fl oz | 1.8014 cup |
| 20 fl oz | 2.4019 cup |
| 25 fl oz | 3.0024 cup |
| 50 fl oz | 6.0047 cup |
| 75 fl oz | 9.0071 cup |
| 100 fl oz | 12.0095 cup |
| 250 fl oz | 30.0237 cup |
| 500 fl oz | 60.0475 cup |
| 1000 fl oz | 120.095 cup |
Exact factor: 1 imperial fluid ounce = 0.1200949926 US cups. Values rounded for display.