Standard Drinks Calculator

About this calculator

A standard drink is a fixed amount of pure alcohol used to compare different beverages on equal footing, since a can of beer, a glass of wine and a shot of spirits all contain wildly different volumes and alcohol percentages but can still deliver the same amount of actual ethanol. Most countries define a standard drink around 10 grams of pure alcohol (Australia, UK, much of Europe), while the US uses a larger 14-gram standard; the calculation itself is straightforward — volume in millilitres × ABV (as a decimal) × ethanol's density (0.789 g/mL) gives grams of alcohol, which is then divided by the standard drink size.

Public health guidelines, low-risk drinking recommendations, and blood-alcohol calculators are all built around standard drink counts rather than raw serving sizes, because "one drink" means wildly different things depending on whether it's a 5% beer, a 13% wine, or a 40% spirit poured generously. Bartenders, health professionals and anyone tracking their own intake use standard-drink conversions to compare servings consistently, since a large glass of strong wine can easily equal two or more standard drinks.

This calculator converts a drink's volume and ABV into both the international standard drink count (10 g) and the US standard drink count (14 g).