Malt liquor is a type of mass market beer with high alcohol content, most closely associated with North America. Legally, it often includes any alcoholic beverage with 5% or more alcohol by volume made with malted barley. In common usage, it refers to beers of high alcohol content, generally above 6%, which are made with ingredients and processes resembling those for American-style lagers.

Alcohol by volume is a standard measure of how much alcohol is contained in a given volume of an alcoholic beverage. It is defined as the number of millilitres (mL) of pure ethanol present in 100 mL of solution at 20 °C (68 °F). The number of millilitres of pure ethanol is the mass of the ethanol divided by its density at 20 °C (68 °F), which is 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.