Imperial fluid ounce fl oz

Symbolfl oz
SystemImperial
QuantityVolume
Value in SI28.4130625 mL (exact)
Defined / adopted1824

About the Imperial fluid ounce

The imperial fluid ounce is one 160th of an imperial gallon, exactly 28.4130625 millilitres. It was chosen so that a fluid ounce of water weighs about one avoirdupois ounce. It is roughly 4 per cent smaller than the US fluid ounce.

Related Units