Alcohol proof is a measure of the content of ethanol (alcohol) in an alcoholic beverage. The term was originally used in England and from 1816 was equal to about 1.75 times the percentage of alcohol by volume (ABV). The United Kingdom today uses ABV instead of proof. In the United States, alcohol proof is defined as twice the percentage of ABV. The definition of proof in terms of ABV varies from country to country.

An alcoholic beverage is a drink that contains ethanol, a type of alcohol and is produced by fermentation of grains, fruits, or other sources of sugar. The consumption of alcoholic drinks, often referred to as "drinking", plays an important social role in many cultures. Alcoholic drinks are typically divided into three classes—beers, wines, and spirits—and typically their alcohol content is between 3% and 50%.