A single gin and tonic (25 ml of gin at 40% ABV with 125 ml of regular tonic) comes to roughly 80 to 95 calories, depending on how much sugar is in your tonic. Make it with slimline tonic and it drops to about 55–60. A double with regular tonic lands around 145–175.
Those ranges are wider than most calorie charts suggest, and there is a good reason for that: in the UK, "regular" tonic is not one thing any more. Below is the full working, a table for singles and doubles, the units, and how a G&T compares with a glass of wine or a pint.
Gin and tonic calories at a glance
Worked out for a gin at 40% ABV. Rounded, because labels vary from brand to brand.
| Tonic | Single 25 ml gin + 125 ml tonic | Double 50 ml gin + 200 ml tonic |
|---|---|---|
| Regular, full sugar (about 8 g per 100 ml) | about 95 kcal | about 175 kcal |
| Regular, lower sugar (about 4–5 g per 100 ml) | about 80 kcal | about 145 kcal |
| Slimline, light or zero | about 55–60 kcal | about 115 kcal |
Ice, a slice of lemon or a sprig of rosemary make no meaningful difference. Juice and cordials do.
Where the calories come from
The gin: about 55 calories per single
Almost all the calories in gin come from the alcohol itself. A distilled gin has no fat, no protein and, in the vast majority of cases, no sugar. Alcohol provides about 7 calories per gram.
The maths: 25 ml of gin at 40% ABV holds 10 ml of pure alcohol. Alcohol weighs about 0.79 g per ml, so that is just under 8 g, which times 7 gives about 55 calories. A double is about 110. Gin and vodka at the same strength come out virtually identical, which we cover in gin vs vodka: what the difference really is.
The tonic: anywhere from almost nothing to about 32 calories per 100 ml
This is where the numbers move. Full-sugar tonic carries around 8 g of sugar per 100 ml, which is about 32 calories. Slimline and zero tonics are sweetened differently and contain close to none.
In between sits a category most calorie charts ignore. Since the Soft Drinks Industry Levy came in during 2018, drinks with 5 g of sugar or more per 100 ml are taxed, and several well-known tonics were reformulated to sit at or below that line. So the "regular" tonic in your fridge may well be lighter than the one the chart assumed. Check the label: the sugar per 100 ml tells you almost everything.
Units: what a G&T actually counts as
- A single (25 ml) of gin at 40% ABV is 1 unit.
- At 37.5% ABV, a common strength in the UK, it is just under 1 unit.
- A double (50 ml) is 2 units.
The UK Chief Medical Officers' low-risk guideline is not to regularly drink more than 14 units a week, spread over several days. Strength matters for calories too: a gin at 47% has about 17% more calories per measure than one at 40%, and a navy strength gin at 57% has over 40% more.
G&T vs wine vs beer
Measure for measure, a single G&T is one of the lighter drinks at the bar. Rough figures:
| Drink | Serve | Calories, roughly |
|---|---|---|
| Single G&T, slimline tonic | 25 ml gin | 55–60 |
| Single G&T, regular tonic | 25 ml gin + 125 ml tonic | 80–95 |
| Medium glass of wine, 12.5% | 175 ml | 130–160 |
| Double G&T, regular tonic | 50 ml gin + 200 ml tonic | 145–175 |
| Pint of lager, 4% | 568 ml | 180–200 |
The catch is the double. Many bars pour 50 ml as standard, and a double with full-sugar tonic is right up there with a large glass of wine.
How to make a lighter G&T that still tastes like one
- Slimline tonic. The single biggest saving, up to about 60 calories on a double. The quinine bitterness comes through more sharply without the sugar, which works well with citrus-led gins and less well with very delicate ones.
- Single, not double. Obvious, but it halves the gin calories. Keep the ratio sensible (roughly 1:3 to 1:5) so it doesn't turn into flavoured water.
- Fill the glass with ice. It doesn't cut calories, but a properly iced G&T stays cold and undiluted for longer, so you drink it more slowly. It is step one in our guide to the perfect gin and tonic.
- Gin and soda. Soda water brings the drink down to the gin's calories alone, but without quinine it is a different drink, crisper and without the bitter edge.
Is gin and tonic fattening?
A single G&T on its own is a modest number. What catches people out is that alcohol calories are "empty" (no nutrients), that the body deals with alcohol before anything else, and that drinks rarely come alone: there's the second round and the crisps. A G&T does not burn fat, and it isn't a diet drink. It is simply one of the lower-calorie options, provided you actually count it. If you are managing your weight or a health condition, the person advising you is the right one to ask; this page does the arithmetic, not medical advice.
And GIN NIRO?
GIN NIRO is bottled at 40% ABV, so it sits exactly on the numbers in the table: about 55 calories of alcohol per single, 110 per double. It is a Sicilian gin built on Zibibbo grapes and citrus peel, and its bright citrus profile holds up well against slimline tonic, where the sharper bitterness can flatten softer gins. Our house serve is the Niro Tonic.
If you'd like to try it: discover GIN NIRO, the Sicilian craft gin made with Zibibbo grapes. We ship to the UK.
Frequently asked questions
How many calories are in a gin and tonic?
A single (25 ml of 40% gin with 125 ml tonic) is about 80–95 calories with regular tonic and 55–60 with slimline. A double with 200 ml of regular tonic is about 145–175.
How many calories are in a shot of gin?
About 55 calories in a 25 ml single at 40% ABV, and about 52 at 37.5%. A double is roughly 110.
Is gin and tonic healthier than wine?
Per serve, a single G&T has fewer calories than a medium glass of wine (175 ml, roughly 130–160). A double with full-sugar tonic is about the same as that glass of wine. Both are alcohol, and the units are what matter most.
Is gin the lowest-calorie drink?
Among spirits, gin, vodka and other 40% spirits are all about the same per measure. The mixer decides the rest: with soda or slimline tonic, a single gin is one of the lowest-calorie drinks you can order.
Does slimline tonic change the taste?
Yes. Without sugar the quinine bitterness is more pronounced and the drink tastes drier. Citrus-forward gins handle it best.
