Alcohol units calculator
Enter a drink's strength and size to see its units, then how many units a week you drink against the 14-unit guideline, with the calories and yearly cost.
How it works
A unit of alcohol is a fixed amount of pure alcohol, and the sum is simple: the drink's strength as a percentage, multiplied by its volume in millilitres, divided by 1,000. So a 568 ml pint at 5% is 2.84 units, and a 175 ml glass of 13% wine is 2.28 units. The tool works out the units in one of your drinks, multiplies by how many you have in a week, and compares the total to the 14-unit low-risk guideline set by the UK Chief Medical Officers.
It also shows two often-ignored costs. Alcohol carries about 7 calories a gram, so the weekly units convert into a yearly calorie figure that surprises most people, and at your typical price the drinks add up to a clear annual spend. Neither is a judgement; they are simply the numbers. If the weekly total sits above 14 units, spreading drinking across more days and keeping several drink-free days is the standard NHS advice for bringing it down.
Worked example
Suppose you have ten pints of 5% lager a week, at £4.50 each. Each pint is 5 times 568 divided by 1,000, which is 2.84 units, so ten pints is 28.4 units a week, well above the 14-unit guideline. Those pints carry about 81,640 calories over a year and cost £2,340.00. Halving the number would bring the units close to the guideline and save roughly half that money and those calories.
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.