How many units in a gin and tonic
A single gin and tonic with 25 ml of 40% gin is 1.0 UK unit. A double with 50 ml is 2.0. Count the spirit, not the tonic.
Spirit ml × ABV ÷ 1000 = UK units. A 25 ml measure at 40% is 1.0 unit, about 7.9 g of alcohol and roughly 56 kcal from ethanol alone.
Single measure (25 ml gin)
UK pubs usually pour 25 ml for a single spirit. Gin is often 37.5% or 40%; premium bottles may be 43% or higher.
| ABV | UK units | FR verres (10 g) | US drinks (14 g) | AU drinks (10 g) | CA drinks (13.45 g) | Grams | kcal | % of UK week (14) | % of FR week (10) |
|---|---|---|---|---|---|---|---|---|---|
| 37.5% | 0.9 | 0.7 | 0.5 | 0.7 | 0.5 | 7.4 | 53 | 6.7% | 7.4% |
| 40% | 1.0 | 0.8 | 0.6 | 0.8 | 0.6 | 7.9 | 56 | 7.1% | 7.9% |
| 43% | 1.1 | 0.8 | 0.6 | 0.8 | 0.6 | 8.5 | 60 | 7.7% | 8.5% |
Work another pour with the unit calculator. Weekly line: guidelines by country.
Double measure (50 ml gin)
A double is two singles in one glass: 50 ml of gin at 40% is 2.0 UK units, the same alcohol as two separate singles.
| ABV | UK units | FR verres (10 g) | US drinks (14 g) | AU drinks (10 g) | CA drinks (13.45 g) | Grams | kcal | % of UK week (14) | % of FR week (10) |
|---|---|---|---|---|---|---|---|---|---|
| 37.5% | 1.9 | 1.5 | 1.1 | 1.5 | 1.1 | 14.8 | 105 | 13.4% | 14.8% |
| 40% | 2.0 | 1.6 | 1.1 | 1.6 | 1.2 | 15.8 | 112 | 14.3% | 15.8% |
| 43% | 2.2 | 1.7 | 1.2 | 1.7 | 1.3 | 17.0 | 120 | 15.4% | 17.0% |
Log the gin measure, not one drink.
Common questions
How many units in a single gin and tonic?
1.0 UK unit if the pub uses 25 ml of 40% gin (25 × 40 ÷ 1000 = 1.0). The tonic is not counted unless it is an alcoholic mixer.
How many units in a double gin and tonic?
2.0 UK units for 50 ml of 40% gin (50 × 40 ÷ 1000 = 2.0). A double is two single measures of spirit in one glass.
Does slimline tonic change the units?
No. Standard and diet tonic contain negligible alcohol. The units come from the gin (or other spirit), not from the mixer.
How much of the weekly guideline is a double G&T?
50 ml of 40% gin is 14.3% of the UK 14-unit week.