ABV to Proof Converter: What Does Proof Mean?
In the United States, proof is twice the alcohol by volume: the federal definition is “the ethyl alcohol content of a liquid at 60 degrees Fahrenheit, stated as twice the percentage of ethyl alcohol by volume” (27 CFR 5.1).
ABV to proof converter (US)
Sources: 27 CFR 5.1: definition of proof (read 3 Nov 2026).
Examples
- 40% ABV = 80 proof (most vodka, gin, whiskey and rum)
- 50% ABV = 100 proof
- 20% ABV = 40 proof
Some other countries used different proof systems in the past; on modern labels the ABV percentage is the figure to compare.
General information only, not medical or legal advice. If you are worried about your drinking, talk to a doctor or see our support pages. Never drink and drive.