Cocktail ABV Calculator
Work out how strong a cocktail really is: add each ingredient's volume and ABV, choose the ice dilution, and get the final alcohol percentage, standard drinks and UK units.
Add at least one ingredient with a volume — the strength updates as you type.
- Final ABV
- 29.5%
- Strength
- Strong
- In the glass
- 87.5 ml
- Pure alcohol
- 25.8 ml
- Alcohol (g)
- 20.4 g
- US drinks
- 1.45
- UK units
- 2.58
- Undiluted
- 36.9%
Estimates only — please drink responsibly and never drink and drive.
How it works
A cocktail's strength is a weighted average of its ingredients. The calculator uses the
standard alcohol-balance formula:
ABV = Σ(volume × ABV) ÷ (total volume × (1 + dilution)). Every ingredient's
volume is multiplied by its own ABV to get the millilitres of pure ethanol it contributes,
those are added up, and the sum is divided by the finished volume of the drink. Non-alcoholic
ingredients such as juice, syrup, soda or espresso are entered at 0% — they add volume and so
pull the strength down.
Ice matters more than most people expect. Stirring a drink to temperature adds roughly 20–25% of its volume in melt water, a hard shake adds about 25–30%, and a tall highball built over cubes picks up around 10% while you drink it. Pick the preparation method and the dilution is added as extra volume before the final ABV is worked out — that is why a Martini poured at about 37% neat lands near 29% in the glass. Set it to 0% if you want the "in the mixing tin" number.
The serving figures use the official definitions: a US standard drink is 14 g of pure ethanol and a UK unit is 10 ml of pure ethanol, with ethanol taken at a density of 0.789 g/ml. One US fluid ounce is 29.5735 ml. The strength label is a rough band: under 5% is very light, under 10% is beer strength, under 20% is wine strength, and anything above 30% is spirit-forward. These are all estimates — real dilution depends on your ice, technique and timing, bottled spirits vary from their label, and nothing here is medical advice. Presets for a dozen classics are built in as starting points — swap in your own bottle strengths for an exact answer. Everything is computed in your browser with plain JavaScript: no recipe you type is uploaded, stored or shared, and there are no ads or sign-ups.
Frequently asked questions
How do you calculate the ABV of a cocktail?
Multiply each ingredient's volume by its own ABV to get the pure ethanol it contributes, add those up, then divide by the finished volume of the drink — including the water that melts in from the ice. Written out that is ABV = Σ(volume × ABV) ÷ (total volume × (1 + dilution)). A Dry Martini of 60 ml gin at 40% plus 10 ml dry vermouth at 18% holds 25.8 ml of ethanol in 70 ml of liquid, so it is 36.9% in the mixing tin; stirred to a typical 25% dilution the finished 87.5 ml drink is 29.5% ABV. Averaging the two ABV numbers instead of weighting them by volume is the classic mistake and gives a badly wrong answer.
How much does ice dilute a cocktail?
Roughly 20–25% of the drink's volume for a stirred cocktail brought to temperature, about 25–30% for a hard shake, and around 10% for a tall highball built over cubes and sipped. Those figures are averages — colder, larger, drier ice and a shorter stir give less water, while small wet cubes and a long stir give more. This calculator adds the dilution as extra volume before working out the final strength and also shows the undiluted number, so you can see both the mixing-tin figure and what actually reaches the glass.
How many standard drinks are in a cocktail?
Count the pure alcohol, not the number of glasses. A US standard drink is 14 grams of pure ethanol and a UK unit is 10 millilitres of pure ethanol, and ethanol weighs about 0.789 g/ml. The 25.8 ml of ethanol in a Dry Martini is therefore 20.4 g — about 1.45 US standard drinks or 2.58 UK units, so a single Martini is closer to a drink and a half than to one drink. The calculator shows both figures, and dividing by the number of servings lets you check a batched punch or pitcher. These are estimates for information only, not medical advice.