Alcohol Units Calculator
Work out how many alcohol units are in a drink from its volume and strength.
Counting units, not just drinks
An alcohol unit is a standard measure of the pure alcohol in a drink, which lets you compare a small strong drink against a large weak one on the same scale. This works out the units in a drink from its volume and its strength, so you can track intake against guidelines more meaningfully than by counting drinks, since drinks vary enormously in size and strength.
Enter the volume and the percentage strength, and see the units.
Why a drink is often more than one unit
People routinely underestimate their intake because a single glass or bottle is frequently more than one unit — a large glass of wine or a strong craft beer can be several. The unit count depends on both how much liquid and how strong it is, which is exactly what makes eyeballing it unreliable. This is a factual calculation to help you understand a drink in standard terms; it is not health advice, and guidance on sensible limits is a matter for official health sources and, where relevant, your doctor.
Frequently asked questions
Why is one drink often more than one unit?
Because units depend on both the volume and the strength — a large glass of wine or a strong beer can be several units.
Does this tell me a safe amount to drink?
No — it only calculates the units in a drink. Guidance on sensible limits comes from official health sources.
Is anything uploaded?
No. The calculation happens in your browser.