How to Calculate Fermentation ABV
What is Fermentation ABV?
Alcohol by volume (ABV) is calculated from starting and finishing gravity readings. The gravity drop indicates how much sugar was converted to alcohol by fermentation.
Formula
ABV ≈ (OG - FG) × 131.25, where OG/FG are original/final gravity
Step-by-Step Guide
- 1Measure original gravity (OG) before fermentation
- 2Measure final gravity (FG) after fermentation
- 3Apply formula to estimate ABV percentage
Worked Examples
Input
OG = 1.060, FG = 1.010
Result
ABV ≈ 6.5%
(0.050) × 131.25
Common Mistakes to Avoid
- ✕Using Plato instead of specific gravity
- ✕Not controlling fermentation temperature
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