About the Alcohol Units Calculator
This alcohol units calculator turns any drink into UK alcohol units, grams of pure alcohol and US standard drinks. Pick a common drink such as a pint of lager or a large glass of wine, or enter your own volume and strength (ABV), then say how many you have per session and how many sessions per week.
It is useful for checking your weekly total against the UK Chief Medical Officers’ low-risk guideline of no more than 14 units a week, for comparing drinks of different strength, and for keeping track during Dry January or a cut-down plan. One UK unit is 10 ml (8 g) of pure alcohol; a US standard drink is 14 g, so the same pint counts as fewer US drinks than UK units.
Real drinks vary: craft beers are often 5–7% and home-poured wine glasses are frequently larger than 175 ml. If you know the exact ABV on the label, use the custom option for the most accurate count.
With the default inputs, the units per session is 6.8. Change any value above to recalculate instantly.
How to use the alcohol units calculator
- 1Choose a common drink or select “Custom” and enter the volume and ABV from the label.
- 2Enter how many of that drink you have in a typical session.
- 3Enter how many sessions you have per week.
- 4Read the units per session and per week, and compare with the 14-unit guideline.
Formula and method
A UK unit is 10 ml of pure alcohol. Multiplying the drink volume in millilitres by its ABV percentage and dividing by 1,000 gives the units in one drink; multiplying by drinks per session and sessions per week gives your totals.
Grams of alcohol use the density of ethanol (0.789 g/ml), so one UK unit is about 7.9 g (commonly rounded to 8 g). US standard drinks divide grams by 14, and calories use 7 kcal per gram of alcohol, ignoring sugars and carbohydrates in the drink.
- volume
- Drink size in millilitres
- ABV
- Alcohol by volume, as a percentage
- Units
- UK alcohol units (10 ml of pure alcohol each)
Worked examples
Three pints of 4% lager, twice a week
A 568 ml pint at 4% contains 568 × 4 ÷ 1,000 = 2.27 units. Three pints is 6.8 units per night, and two nights a week gives 13.6 units — just under the 14-unit guideline. The 53.8 g of alcohol per session equals about 3.8 US standard drinks.
A bottle of 13% wine on four evenings
A 750 ml bottle at 13% holds 750 × 13 ÷ 1,000 = 9.75 units. Four bottles a week is 39 units, almost three times the 14-unit low-risk guideline.
Two 6.5% craft IPAs (440 ml cans)
Each 440 ml can at 6.5% contains 2.86 units, so two cans are 5.72 units — more than two pints of ordinary 4% beer. The alcohol alone supplies about 316 kcal.
Frequently asked questions
How many units are in a bottle of wine?+
A 750 ml bottle of 12% wine contains 9 units and a 13.5% bottle contains about 10 units. A standard 175 ml glass of 13% wine is roughly 2.3 units and a large 250 ml glass is about 3.3 units.
How many units are in a pint of beer?+
A pint (568 ml) of 4% beer or lager is 2.3 units. Stronger 5.2% beers are about 3 units per pint, and many craft IPAs at 6–7% contain 3.4–4 units per pint.
What is the recommended weekly limit for alcohol?+
The UK Chief Medical Officers advise men and women not to drink more than 14 units a week on a regular basis, spread over three or more days, with several drink-free days each week.
What is the difference between a UK unit and a US standard drink?+
A UK unit is 10 ml, or about 8 g, of pure alcohol. A US standard drink is 14 g — roughly 1.75 UK units — so the same drink counts as fewer US standard drinks than UK units.
How long does it take to process one unit of alcohol?+
As a rough guide, the body clears about one unit per hour, but this varies with body size, sex, liver health and food. There is no way to speed it up; coffee or cold showers do not lower blood alcohol.
This tool gives general estimates and is not medical advice. Talk to a doctor or qualified professional about your health, diet or training.