Alcohol by volume

Alcohol by volume is a common measure of the amount of alcohol contained in a given alcoholic beverage. It is defined as the volume the ethanol in the liquid would take if separated from the rest of the solution, divided by the volume of the solution, both at 20 °C (68 °F). Pure ethanol is lighter than water, with a density of 0.78945 g/mL. The alc/vol standard is used worldwide. The International Organization of Legal Metrology has tables of density of water–ethanol mixtures at different concentrations and temperatures.