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Alcohol units calculator
How many units are in your drink? Pick a drink or enter its size and strength to see the UK units, the standard drinks for your country and the grams of pure alcohol. Add how often you have it to see your weekly total.
This calculator needs JavaScript. To work out UK units by hand: strength (ABV %) × volume (ml) ÷ 1,000. A 175 ml glass of 12% wine is 2.1 units.
- Pure alcohol
- UK units
- US standard drinks
- Standard drinks (10 g)
- Your week
Want to see your units add up without doing the maths? LastGlass logs your drinks in a one-minute check-in and shows them in UK units or your country's standard drinks, alongside your alcohol-free days.
Track it free in LastGlassHow to calculate alcohol units
The NHS formula is simple: strength (ABV %) × volume (ml) ÷ 1,000 = units. ABV is the percentage of the drink that is pure alcohol, printed on the label. A pint (568 ml) of 5.2% lager is 5.2 × 568 ÷ 1,000 = 2.95 units.
One UK unit is 10 ml or 8 g of pure alcohol. Other countries count in standard drinks instead: about 14 g in the US and 10 g in Australia and New Zealand. Standard drinks here are worked out from grams of pure alcohol, using 0.789 g per ml.
Units in common drinks
Average figures from the NHS. Check the label: a stronger beer or wine has more units than you might think.
| Drink | UK units |
|---|---|
| Single small shot of spirits (25 ml, 40%) | 1 |
| Alcopop (275 ml, 4.6%) | 1.3 |
| Small glass of wine (125 ml, 12%) | 1.5 |
| Bottle of lager, beer or cider (330 ml, 5%) | 1.7 |
| Pint of lower-strength lager, beer or cider (3.6%) | 2 |
| Standard glass of wine (175 ml, 12%) | 2.1 |
| Can of lager, beer or cider (440 ml, 5.5%) | 2.4 |
| Pint of higher-strength lager, beer or cider (5.2%) | 3 |
| Large glass of wine (250 ml, 12%) | 3 |
| Bottle of wine (750 ml, 13.5%) | 10 |
More detail: how many units in a bottle of wine and how many units in a pint of beer.
The UK weekly guideline
To keep health risks low, the NHS advises men and women not to drink more than 14 units a week on a regular basis. If you do drink that much, spread it over three or more days, and have several drink-free days each week if you want to cut down. 14 units is about 6 pints of average-strength beer or 10 small glasses of lower-strength wine. Guidelines differ by country, and the World Health Organization says no level of drinking is safe for health.
Want to cut down? See how to cut back on alcohol and how many alcohol-free days a week.
Keep track without the maths
LastGlass is a private alcohol tracker for iPhone, iPad and Apple Watch. A one-minute daily check-in records whether alcohol was part of your day, and Drinks and units in Settings shows your drinks in UK units or the standard drinks used in your country. Choose a drink less goal or alcohol-free days, see your calendar, and use I need support now when an urge shows up. The core app is free; no account needed.
Frequently asked questions
How do you calculate alcohol units?
Multiply the strength (ABV, as a percentage) by the volume in millilitres and divide by 1,000. For example, a 175 ml glass of 12% wine is 12 × 175 ÷ 1,000 = 2.1 units. This is the formula the NHS uses.
What is one unit of alcohol?
In the UK, one unit is 10 ml or 8 g of pure alcohol. The NHS says that is around the amount of alcohol the average adult can process in an hour, though this varies from person to person.
How many units a week is safe?
The UK low-risk guideline is no more than 14 units a week on a regular basis for men and women, spread over three or more days, with several drink-free days each week if you want to cut down. The World Health Organization says no level of drinking is safe for health.
What is the difference between a unit and a standard drink?
Both measure pure alcohol, but countries define them differently. A UK unit is 8 g. A US standard drink is about 14 g, and an Australian or New Zealand standard drink is 10 g. So one US standard drink is about 1.75 UK units.
Can I use this to work out if I am safe to drive?
No. How quickly you process alcohol varies a lot from person to person, and units do not tell you your blood alcohol level. The only safe approach is not to drink at all if you are driving.