How alcohol calories are calculated
Almost all of a drink's calories from alcohol come from ethanol itself. Multiplying volume by ABV gives the volume of pure alcohol; multiplying that by ethanol's density gives its weight in grams; multiplying by calories per gram gives the total.
- volume — amount you drank (mL)
- abv — alcohol by volume, % (e.g. beer 5, soju 17)
- 0.789 — ethanol density, g/mL
- 7 — calories per gram of ethanol (Atwater factor)
More detail
Why alcohol calories count separately
Ethanol supplies 7 kcal per gram — more than protein or carbs (4 kcal/g) and close to fat (9 kcal/g) — and the body burns it before other fuel sources. This calculator covers only that alcohol energy; a real drink's mixers, sugar, or carbs (beer's malt sugars, a sweet cocktail's syrup) add calories on top.
Typical drinks by volume and ABV
A 355 mL can of beer at 5% ABV has about 14 g of alcohol (~98 kcal from alcohol alone). A 360 mL bottle of soju at 17% has about 48 g (~338 kcal). A 150 mL glass of wine at 12% has about 14 g (~99 kcal). Change the inputs above to match your actual drink.
Practical tip. This number is alcohol calories only, not the drink's total calories — a sugary cocktail or dark beer can add far more from carbs than from alcohol. If you're tracking intake, add the drink's listed calories rather than relying on this figure alone.
Frequently asked questions
How many calories are in a 355 mL can of beer at 5% ABV?
355 mL × 5% × 0.789 g/mL ≈ 14 g of pure alcohol, and 14 g × 7 kcal/g ≈ 98 kcal from alcohol. The actual can has more total calories once carbohydrates from the malt are included.
How many alcohol calories are in a 360 mL bottle of soju at 17%?
360 mL × 17% × 0.789 g/mL ≈ 48.3 g of pure alcohol, times 7 kcal/g ≈ 338 kcal — enter 360 and 17 above to see the exact figures.
Why is alcohol counted as 7 kcal per gram?
This is the Atwater general factor for ethanol, sitting between carbohydrates/protein (4 kcal/g) and fat (9 kcal/g). It reflects the energy the body can actually extract from ethanol during metabolism.
Does this match the total calories printed on a drink's label?
No — this calculates only the calories from pure alcohol. Sugars, carbs, and mixers (beer's malt, a cocktail's syrup or juice) add calories beyond what's shown here, so a real drink's total is usually higher.