Imperial, Metric, and US Conversions

[jasonr]

Is a fl oz a volume or mass measurement?

 

[subfuscpersona]

Is a fl oz a volume or mass measurement?

Strictly speaking a fluid oz is a measure of volume

Fortunately one fluid oz water (measured by either the US or British Imperial system) is basically equal to one oz by weight.

Liquids with a similar density to water, such as milk, also conform to the conversion that 1 fluid oz (volume) = 1 oz (weight).

If, however, you're measuring a heavier liquid (such as honey), this "equality" doesn''t hold.