Alcohol Units Calculator

ml
%
Health Updated 14 Jun 2026

The Alcohol Units Calculator converts any drink into UK alcohol units and US standard drinks. UK units = volume (mL) × ABV ÷ 1000, and a US standard drink is 14 g of pure alcohol.

  • Uses standard alcohol density (0.789 g/ml).

Formula

UK units = volume × ABV ÷ 1000; US drinks = grams of alcohol ÷ 14
  • One UK unit is 10 mL (8 g) of pure alcohol: UK units = volume (mL) × ABV% ÷ 1000.
  • One US standard drink contains 14 g of pure alcohol, so US drinks = grams of alcohol ÷ 14.
  • Grams of alcohol = volume × ABV as a decimal × 0.789 (ethanol density).
  • Guidelines such as the UK's 14 units/week are a useful reference for keeping drinking within lower-risk levels.

Example Calculation

Inputs
  • Drink Volume: 330 ml
  • Alcohol (ABV): 5 %

A 330 mL beer at 5% ABV is 330 × 5 ÷ 1000 = 1.65 UK units, or about 0.9 US standard drinks (≈13 g of alcohol ÷ 14).

Frequently asked questions

What is one unit of alcohol?
In the UK, one unit is 10 mL (8 g) of pure alcohol — the amount an average adult can process in about an hour.
What is a US standard drink?
A US standard drink contains 14 g of pure alcohol, roughly a 12 oz beer, 5 oz wine, or 1.5 oz of spirits.
How are units calculated?
UK units = drink volume in mL × ABV% ÷ 1000. US drinks divide the grams of alcohol by 14.
How many units are safe?
UK guidelines suggest no more than 14 units per week, spread over several days with alcohol-free days.
Why do UK units and US drinks differ?
They use different reference amounts of alcohol (8 g vs 14 g), so the same drink yields different numbers in each system.

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