Mash Efficiency Calculator — Mash & Brewhouse Efficiency
Measure how well your mash extracted fermentable sugars from the grain and calculate true brewhouse efficiency.
Post-boil values (for brewhouse efficiency)
How We Calculate This
This calculator compares the gravity points you actually collected to the theoretical maximum from your grain bill.
Mash efficiency
Actual points = (Pre-boil SG − 1) × 1000 × Pre-boil volume (gallons)
Potential points = Grain weight (lbs) × PPG
Mash efficiency = Actual points / Potential points × 100
Brewhouse efficiency
Brewhouse efficiency uses post-boil gravity and the volume transferred to the fermenter (post-boil volume minus trub loss) as the numerator, with the same potential points as the denominator. This captures all system losses from mash to fermenter.
Frequently Asked Questions
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Last updated: March 2026
All calculations are estimates. Always verify values and adjust based on your equipment and ingredients.