ABV Calculator: Alcohol by Volume for Homebrew
Calculate the alcohol percentage for homebrewing beer or wine.
How ABV is Calculated
Alcohol is produced when yeast consumes sugar. By measuring the density of the liquid before fermentation (Original Gravity) and after (Final Gravity), we can calculate how much sugar was converted into alcohol.
Standard Formula
- Formula: (OG - FG) × 131.25 = ABV%
- Take your hydrometer reading before adding yeast (e.g., 1.050).
- Take your reading after fermentation stops (e.g., 1.010).
- Calculate: (1.050 - 1.010) = 0.040. Then 0.040 × 131.25 = 5.25% ABV.
Homebrew FAQs
What affects the final ABV?
The amount of fermentable sugars (malt extract, honey, sugar) and the attenuation rate of your yeast strain determine the final alcohol content.
Do I need to correct for temperature?
Yes, hydrometers are calibrated to a specific temperature (usually 60°F or 20°C). If your sample is hot, you need to apply a correction factor.