Calculates UK-style alcohol units from a drink’s volume and alcohol by volume (ABV) percentage.
How it works
Drink volume in milliliters is multiplied by ABV percentage and divided by 1,000, following the official UK unit definition.
What this does not include
This does not include the US “standard drink” measure, which is defined differently (14 g of pure alcohol) — this calculator specifically uses the UK unit definition.
How to use this calculator
- Enter the drink’s volume and its ABV percentage.
A worked example
A pint (568 mL) of 4.5% ABV beer → 568 × 4.5 ÷ 1,000 = 2.556 units.
A 175 mL glass of 12% ABV wine → 175 × 12 ÷ 1,000 = 2.1 units.
What the variables mean
| Variable | Meaning |
|---|---|
| Volume (mL) | How much of the drink |
| ABV (%) | Alcohol by volume, printed on the label |
Edge cases worth knowing
A smaller, stronger drink can easily out-unit a larger, weaker one. The 175 mL wine pour above (2.1 units) comes close to the 568 mL beer (2.556 units) despite being roughly a third of the volume, purely because of its higher ABV.
UK units and US standard drinks measure alcohol differently — a UK unit is 10 mL of pure alcohol, a US standard drink is 14 grams, and the two aren’t directly interchangeable without converting between volume and mass.
Frequently asked questions
Why isn’t a “unit” the same as one drink?
Units measure actual alcohol content, not serving count — a large or strong drink can easily be more than one unit even served as a single glass.
Why is a UK unit exactly 10 mL of pure alcohol?
It’s the official measure set by UK health authorities, chosen as a round, easy-to-communicate reference amount for public health guidance.
How is this different from a US standard drink?
A US standard drink is defined as 14 grams of pure alcohol, a different reference amount than the UK’s 10 mL (about 8 grams) — the two aren’t directly interchangeable without conversion.
This calculator is for general informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional for guidance specific to your situation.
