CanadaTier 2
Brewhouse efficiency calculator
Grain bill and measured OG in. Your brewhouse efficiency percentage out.
Free·No sign-up·Last checked 2026-08-27
Formula
Max points = grain_lb × (potential − 1) × 1000
Actual points = (OG − 1) × 1000 × batch_gal
Efficiency% = actual points ÷ max points × 100
Worked example. 4.5 kg grain (9.92 lb) at 1.037 potential, 19 L (5.02 gal) batch, OG 1.050 → 251 actual points ÷ 367 max points = 68.4%.
Method
Grain kilograms and batch litres converted to pounds and gallons internally
Grain potential (points per pound per gallon) is an imperial-unit convention still used on malt spec sheets everywhere, including Canada. Rather than guess a new metric constant, this calculator converts your kilogram and litre inputs to pounds and gallons, runs the standard formula, and reports the resulting percentage — which doesn't depend on which unit system was used to get there.
Questions
Most home all-grain setups land between 65% and 80%. Below 60% usually points to a crush that's too coarse or a stuck/channeled sparge; above 85% is unusual outside commercial-scale equipment.
Malt spec sheets worldwide, including in Canada, still quote potential as the specific gravity a pound of grain gives in a gallon of water — 1.037, or 37 points per pound per gallon, is a common base-malt default. This calculator converts your kilograms and litres to pounds and gallons internally, applies that potential, then reports a unit-independent efficiency percentage.