🌾 Mash Efficiency Calculator
Enter your measured OG, grain weight and batch volume to see your mash efficiency percentage.
Mash / brewhouse efficiency
69.4%
Good, typical all-grain efficiency
Efficiency = the gravity points you got ÷ the most the grain could give. Actual points are (OG − 1) × 1000; the maximum is grain weight × its potential (PPG, ~36–37 for base malt) ÷ batch volume in gallons. Most all-grain brewers land at 65–80%. A finer crush, correct mash pH, full 60-minute mash and efficient sparge all raise it. 🔒 In your browser.
How the mash efficiency calculator works
Mash efficiency is how much of the sugar locked in your grain you actually extracted into the wort. It's the gravity points you measured divided by the maximum the grain could give: actual points are (OG − 1) × 1000, and the maximum is grain weight × its potential (PPG, points per pound per gallon — about 36–37 for base malt) divided by the batch volume in gallons. The tool converts metric inputs and returns the efficiency percentage with a quick verdict.
Most all-grain homebrewers land between 65% and 80%. If yours is low, the usual culprits are too coarse a crush, mash pH out of the 5.2–5.6 range, too short a mash, or an inefficient sparge. Knowing your typical efficiency lets you scale a recipe's grain bill to hit the OG you want. Extract and partial-mash brews behave differently.
Frequently asked questions
What is mash efficiency?
The percentage of the grain's available sugar you extracted into the wort. It's the measured gravity points ÷ the maximum the grain could yield. Most all-grain brewers get 65–80%; consistency matters more than a high number.
How do I calculate brewhouse efficiency?
Efficiency = ((OG − 1) × 1000) ÷ (grain lb × PPG ÷ volume gal) × 100. For 1.050 OG from 10 lb of 36-PPG malt in 5 gallons: 50 ÷ (72) = about 69%. This tool does the maths and unit conversion.
What is a good mash efficiency?
Around 70–75% is a solid, typical figure for all-grain brewing. Below ~60% suggests something to improve; above ~85% is unusually high and worth double-checking your measurements.
How do I improve mash efficiency?
Crush the grain finer (without shredding the husks), keep mash pH near 5.2–5.6, give a full 60-minute mash at the right temperature, stir well, and sparge slowly and thoroughly. Water-to-grain ratio and vorlauf also help.
What is PPG?
Points per pound per gallon — a malt's sugar potential. Base malts are about 36–37 PPG (a pound in a gallon of water at 100% efficiency would read ~1.037). Specialty malts vary; suppliers list each grain's potential.