Quick answer: alcohol units = volume (ml) × ABV (%) ÷ 1,000. Use our free Alcohol Units Calculator to track units across beer, wine, and spirits instantly.
The Formula
One unit equals 10ml (or 8g) of pure alcohol. A pint of 4% beer (568ml) contains about 2.3 units. A 175ml glass of 12% wine contains about 2.1 units. A single 25ml shot of 40% spirit contains 1 unit.
UK NHS Guidelines
The NHS recommends no more than 14 units per week for both men and women, spread across three or more days, with several alcohol-free days each week.
Frequently Asked Questions
How many units are in a bottle of wine?
A standard 750ml bottle at 13% ABV contains about 9.75 units.
Is this the same as blood alcohol content?
No — units measure total alcohol consumed, not your current blood alcohol level, which depends on body weight, time, and metabolism.
Does this account for different drink strengths?
Yes, enter the actual ABV% of your specific drink for an accurate unit count.
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Open the Tool →Worked example: calculate units in a drink
The UK unit formula is units = ABV (%) × drink volume (ml) ÷ 1,000. A 568 ml drink at 5.2% ABV contains about 5.2 × 568 ÷ 1,000 = 2.95 units. A 175 ml glass of wine at 12% ABV contains about 2.1 units. The pour size and the strength both change the result, so use the label and the actual serving size rather than a generic “glass” estimate.
One UK unit represents 10 ml (8 g) of pure alcohol. Units are a way to describe the amount consumed; they do not predict an individual person’s blood alcohol level or how quickly alcohol is cleared. The NHS notes that alcohol affects people differently. Do not use a unit calculation to decide whether it is safe to drive or operate machinery.
Keep the result in context
This calculation follows the UK unit system and may not match standard-drink definitions used in other countries. For health guidance, check the current advice from your local health authority. The formula and unit definition are described by the NHS alcohol-units guide.
Check the serving size before multiplying
A label may show ABV but not the number of units in your poured serving. Measure the volume in millilitres, multiply by the ABV percentage, then divide by 1,000. If a bottle is shared, calculate the portion actually consumed rather than the full container. The NHS formula is a measurement convention for the UK; other countries may define a “standard drink” differently. A unit total cannot establish that a person is safe to drive, and it should not be used to estimate an individual’s alcohol level.