Mash Efficiency Calculator

How it is calculated

Efficiency compares the sugar actually in the wort with the most the grain could give. actual points = (OG − 1) × 1000 × volume and maximum points = grain weight × PPG, then efficiency % = actual / maximum × 100. OG is the measured specific gravity of the wort (written as 1.050), volume is in US gallons, grain weight is in pounds, and PPG is the grain's potential in points per pound per gallon. The tool uses these US units only, so convert litres and kilograms first. OG must be above 1 and the other three values above zero. Because a mash cannot give more than the grain holds, any input set that works out above 100 % (usually a unit or typing slip) shows no result instead of an impossible figure. Use a weighted average PPG if you mix grains.

Common mistakes

• Entering the gravity as 50 or 1050 instead of 1.050. The field expects the specific-gravity form; 50 would imply far more than 100 % and shows no result.
• Using litres and kilograms. The tool expects US gallons and pounds, so a 21 L batch must be entered as about 5.5 gal; 21 with 11 lb of grain gives over 100 % and no result.
• Using the volume at the end of the boil or in the fermenter instead of the wort volume matching the gravity reading. Gravity and volume must be from the same point.
• Reading gravity from a hot sample without temperature correction. A hot wort reads too low and understates your efficiency.
• Entering one grain's PPG when the bill has several, such as a high-potential base malt plus low-potential specialty malt. Use a weighted average or the figure will be off.