Standard Drink Calculator
Find out how many standard drinks are in a beverage based on its volume and alcohol percentage.
What is a standard drink?
A standard drink is a reference unit used to describe how much pure alcohol a beverage contains, so drinks of different sizes and strengths can be compared fairly. In the United States, one standard drink is defined as containing about 14 grams (0.6 fl oz) of pure alcohol, which is roughly a 12 oz regular beer at 5% ABV, a 5 oz glass of wine at 12% ABV, or a 1.5 oz shot of 40% spirits.
How this calculator works
The calculator converts your beverage’s volume and alcohol-by-volume (ABV) percentage into grams of pure alcohol using the density of ethanol (about 0.789 g/mL), then divides by 14 grams to express the result in standard drinks. Multiplying by the number of drinks gives your total for the session.
Standard drink definitions vary by country (some use 10 grams as the reference unit), and this calculator uses the U.S. standard. This tool is for general informational and educational purposes only and is not a measure of impairment, blood alcohol content, or safety to drive.