How to convert US fluid ounces to millilitres
Both units measure volume, so no ingredient is involved. The converter turns your input into a shared base unit (millilitres) and divides by the target unit's factor. One US fluid ounce is 29.5735 millilitres; one millilitre is 1 millilitres.
The full factors are kept until the final display is rounded. Use the "more precision" line on the result card when you need more decimals, and remember that a rounded kitchen fraction is a convenience rather than an exact equivalent.
Choose the measurement your recipe means
The default cup is US customary at 236.5882365 ml. Metric and Australian cups use 250 ml. A metric tablespoon is 15 ml; an Australian tablespoon is 20 ml. Fluid ounces, pints, quarts and gallons in this interface stay US liquid units whichever cup system you select.
An ounce by weight measures mass; a fluid ounce measures volume. They are different units. If your recipe gives a dry ingredient in ounces, select "Ounces, weight (oz)" and then the ingredient for any conversion to cups. Eight US fluid ounces make a US cup, but that is not a rule for dry ounces.