Original Gravity Calculator — Estimate OG
Estimate your original gravity from grain bill weight, potential extract and brewhouse efficiency.
Points per pound per gallon (e.g. Pale Malt = 37)
How We Calculate This
The OG Formula
Original gravity is estimated using: OG = 1 + (grain_lbs x PPG x efficiency) / (batch_gallons x 1000). The grain weight is converted to pounds, multiplied by the potential extract (PPG) and your efficiency percentage, then divided by the batch volume in gallons.
Understanding PPG
PPG stands for Points Per Pound Per Gallon. Common values: Pale Malt 36-37, Munich 34-35, Crystal 33-35, Wheat 36-37, Pilsner 36-37. These represent the maximum extract potential of each grain.
Frequently Asked Questions
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Last updated: 2025-02-20
All calculations are estimates. Always verify values and adjust based on your equipment and ingredients.