Alcohol Units Calculator
Find out exactly how many units of alcohol are in any drink — enter the ABV percentage, the serving size in ml and how many drinks you had. The calculator compares your total to the UK NHS 14-unit weekly guideline and estimates the calories from the alcohol content.
%
ml
1 unit = 10 ml (8 g) of pure alcohol
- 1
Units per drink
5 % × 500 ml ÷ 1 000 = 2.51 unit = 10 ml pure alcohol; dividing by 1 000 converts ml × % to units. - 2
Total alcohol units
2.5 × 1 = 2.50
How does this calculator work?
Alcohol units = ABV% × volume(ml) ÷ 1000. One unit is 10 ml of pure alcohol. Enter the ABV and serving size to get total units; the calculator compares the result to the UK NHS guideline of 14 units per week and estimates the calorie contribution from alcohol (~56 kcal per unit).
Formula
How this is calculated
One unit of alcohol is defined as 10 ml (8 g) of pure ethanol — the standard used in the UK and many other countries. The formula is simple: multiply the ABV percentage by the volume in millilitres, then divide by 1000. A 500 ml pint of 5% lager contains 5 × 500 / 1000 = 2.5 units; a 250 ml glass of 12% wine contains 3 units; and a 25 ml shot of 40% spirit contains 1 unit.
The UK NHS recommends that both men and women drink no more than 14 units per week, spread over at least three days, with several alcohol-free days each week. The risk-band meter maps your total against these thresholds: up to 14 units is within the low-risk guideline, 14–17.5 units represents a moderate excess, and above 17.5 units is consistently classified as high-risk drinking by UK health agencies.
Alcohol contributes roughly 7 kcal per gram of pure ethanol — about 56 kcal per unit. The calorie figure shown covers only the energy from the alcohol itself; sugary mixers, craft-beer carbohydrates and cream liqueurs add considerably more. Guidelines and unit definitions vary by country (the WHO, EU and US all use slightly different "standard drink" sizes), so the 14-unit figure is specific to UK NHS advice.
Frequently asked questions
One UK unit equals 10 ml (8 g) of pure ethanol. Practical equivalents: a 25 ml shot of 40% spirit, a 330 ml can of 3% beer, or a third of a pint of 5% lager each contain roughly one unit.
In the UK, the NHS recommends no more than 14 units per week for both men and women. Older guidance used higher limits for men; the current recommendation was lowered in 2016 to reflect evidence that any amount of alcohol carries some health risk.
Fermentation strength, sugar content and whether spirits are diluted all affect final ABV. Standard lagers range from 3% to 8%, wines from 10% to 16%, and spirits from 35% to 70% or above. Always check the label for an accurate calculation.
Also known as
TG we-Calculate Editorial Team. (2026). Alcohol Units Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/alcohol-units-calculator
TG we-Calculate Editorial Team. "Alcohol Units Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/alcohol-units-calculator.
TG we-Calculate Editorial Team, "Alcohol Units Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/alcohol-units-calculator
@misc{wecalculate_alcohol_units_calculator, title = {Alcohol Units Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/alcohol-units-calculator}}, year = {2026}, note = {TG we-Calculate} }
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