Alcohol units calculator
This calculator works out how many units are in a drink from its strength and volume, then totals units drunk in a week and compares that figure with the NHS low risk drinking guideline of 14 units a week. It also estimates yearly calories and cost. Figures are general information, not advice to drink less.
How many units are in a drink?
A unit of alcohol is calculated by multiplying a drink's strength, its ABV percentage, by its volume in millilitres, then dividing by 1,000.
| Drink | Approximate units |
|---|---|
| Pint of 5% beer (568 ml) | 2.8 |
| 175 ml glass of 13% wine | 2.3 |
| 25 ml single of 40% spirit | 1 |
The calculator multiplies the units in one drink by how many drinks are had in a week, then compares the weekly total against the NHS low-risk guideline of 14 units a week.
It also converts the weekly units into an estimated yearly calorie figure and an estimated yearly cost, based on the price entered.
What would this look like for an example week of drinking?
Take ten pints of 5% lager a week at £4.50 each.
Each pint comes to 2.8 units, so ten pints total 28.4 units a week.
That is above the NHS guideline of 14 units a week.
Those pints add up to about 81,640 calories and £2,340.00 over a year.
These are estimates rather than advice on how much to drink.
Common questions
How many units are in a drink?
Units are the strength (ABV per cent) times the volume in millilitres, divided by 1,000. A pint of 5% beer is 5 times 568 divided by 1,000, which is about 2.8 units. A 175 ml glass of 13% wine is around 2.3 units, and a 25 ml single of 40% spirits is 1 unit.
How many units a week is safe?
The UK Chief Medical Officers advise keeping to no more than 14 units a week to keep health risks low, whether you are a man or a woman. It is better to spread those units across three or more days than to save them for one or two heavy sessions.
How many calories are in alcohol?
Pure alcohol has about 7 calories per gram, close to fat, and those calories carry no useful nutrition. A large glass of wine can hold as many calories as a chocolate bar. Cutting back is one of the quicker ways to reduce calorie intake.
Does a drink-free day help?
Yes. Regular drink-free days give your liver time to recover and make it easier to stay under 14 units a week. The NHS suggests several alcohol-free days each week as a simple way to cut your overall intake.
Is 14 units the same for everyone?
The 14-unit weekly guideline applies to adults in general. There is no completely safe level, and pregnant women are advised not to drink at all. Some medicines and health conditions also mean you should drink less or avoid alcohol.
What would this look like for an example week of drinking?
Ten pints of 5% lager a week at £4.50 each comes to 2.8 units per pint, so the weekly total is 28.4 units, above the NHS guideline of 14 units a week. Those pints add up to about 81,640 calories and £2,340.00 over a year. These figures are general information rather than advice on how much to drink.
Sources & Rate Verification
Rates verified against official statutory guidance on 6 September 2026.