The exact conversion
One US fluid ounce is 29.5735 mL. Eight of them make a cup (236.588 mL), which is why American recipes use 8 oz and 1 cup interchangeably for liquids.
US versus imperial fluid ounces
- US fl oz: 29.5735 mL
- Imperial fl oz: 28.413 mL — about 4% smaller
- UK recipes are usually metric now, so fluid ounces often signal an older book
- Nutrition labels in the US use fluid ounces for drinks
Baking applications
Vanilla, extracts and colourings are often given in fluid ounces; a 2 oz bottle is 59 mL, roughly 12 teaspoons. Liqueurs and syrups follow the same maths.
When weight is better
For anything thick — honey, condensed milk, nut butter — fluid ounces are measured in a jug and losses to sticking make them unreliable. Weigh instead and convert with the cups-to-grams tool.
Frequently Asked Questions
Is 1 fl oz the same as 1 oz?
No. 1 fl oz is volume (29.6 mL); 1 oz is weight (28.3 g).
How many mL is 8 fl oz?
236.6 mL — exactly one US cup.
Why is a UK fluid ounce different?
Historical gallon definitions differ; the imperial fl oz is 28.413 mL.
Privacy & Your Data
KitchenCalcHub runs entirely in your browser. Recipes, measurements and conversions are processed on your device and never uploaded — there is no server to store them.