Standard Drink Sizes by Country: The Complete Global Reference

Standard drink definitions were developed independently by each country's health authorities, usually around familiar local serving sizes. The UK's 8g unit reflects a small pub measure of spirits, Australia's 10g standard drink reflects local labelling practice, and the US 14g definition maps neatly to a 12 oz can of regular beer. These definitions were made to be locally intuitive, not internationally interchangeable.

The practical consequence is that health guidance expressed in standard drinks cannot be compared by the headline number alone. Fourteen UK units equals 112g of pure alcohol, while fourteen US standard drinks equals 196g. The same number can represent a very different dose.

This matters for legal and health reference pages too. Use alcohol laws by country for legal BAC limits, but use standard drink definitions when comparing health guidance or drink counts across countries.

Because standard drink sizes differ, weekly guidelines expressed in drinks or units represent different pure alcohol totals. The table below converts major guidelines into grams per week, the only meaningful comparison. For the calorie and body-weight side of these totals, see alcohol and weight loss.

The United Kingdom uses units rather than standard drinks. One unit equals 8 grams of pure alcohol. The formula is simple: volume in millilitres multiplied by ABV percentage, then divided by 1,000. A 568ml pint of 4% beer is 568 x 4 / 1,000 = 2.3 units.

The UK Chief Medical Officers' guideline recommends that both men and women drink no more than 14 units per week, spread across several days with alcohol-free days. Fourteen UK units equals 112g of pure alcohol per week.

Australia defines one standard drink as containing 10 grams of pure alcohol. Unlike many countries, Australia requires alcoholic beverages to display the number of standard drinks on the label, making it easier to track consumption from the package itself.

The Australian Alcohol Guidelines recommend no more than 10 standard drinks per week and no more than 4 standard drinks on any single day. Ten Australian standard drinks per week equals 100g of pure alcohol.

When a BAC calculator asks for number of drinks, it usually assumes one specific standard drink size. If you enter UK units into a US-based calculator without converting, the estimate can be wrong. The safer method is to enter volume and ABV directly. The alcohol content by drink database helps when you do not know the ABV.

The Widmark formula behind BAC estimates works from pure alcohol dose, body weight, sex, and time. The how BAC works guide explains the formula, while the BAC by drinks table shows why local drink definitions matter.