This ABV calculator estimates apparent fermentation, alcohol by weight and volume, US/UK proof, and pure alcohol content for beer.
Food
ABV Calculator
Estimate beer alcohol by weight and volume from original and apparent extract.
Calculator
About this calculator
Formula notes
ABW derives from original and apparent extract reduction, ABV = ABW x (specific gravity estimate), proof scales ABV for US and UK conventions, and content multiplies ABV by volume.
Worked examples
- Example: 12 P original extract, 3 P apparent extract, and 20 liters produce ABW about 3.73%, ABV about 4.78%, and about 956 ml of pure alcohol.
- Original extract 10, apparent extract 2, and 10 liters produce ABW about 3.26%, ABV about 4.16%, and about 416 ml pure alcohol.
How to use it
- Enter original and apparent extract.
- Enter total beverage volume in liters.
- Read fermentation, ABW, ABV, proofs, and alcohol volume.
Frequently asked questions
Are these hydrometer estimates exact?
They rely on a consistent extract formula and average conversions; calibration, dissolved CO2, and sugar type affect precision.
What does proof mean here?
US proof is twice the ABV; UK proof uses the lumber scale. It does not imply drinking safety or exact labeling.
Limits and interpretation
- The formula is a consistent estimate for beer-style extracts; spirits, wine, and other beverages use different conversion conventions.
- Do not use the result to determine drinking safety, legal limits, or product labeling without checking the relevant regulation.