Brewhouse Efficiency Calculator

In short Brewhouse efficiency is how much of the sugar in the grain actually reached the fermenter, and it is the number that decides whether you hit your gravity or come up five points short every single time. The arithmetic rests on one fact: GRAVITY POINTS TIMES LITRES IS THE EXTRACT, and that product does not change when you dilute or boil down — only the two numbers making it up do. Fifty points in 19 litres is the same sugar as 62.5 points in 15.2. Every top-up, boil-off and dilution calculation in brewing is that one identity, and it is what makes every line on this page invertible. Everything is quoted against sucrose, which yields 46 points per pound per gallon. Both of those units are exactly defined, so in metric that is 46 × 3.785411784 ÷ 0.45359237 = 383.9 points per kilo per litre. A pale malt at about 80% of sucrose therefore offers roughly 307 points per kilo per litre, and 4.2 kilos in 19 litres could give 68 points if nothing at all were lost. Get 50 and your efficiency is 73%. EFFICIENCY IS A PROPERTY OF YOUR EQUIPMENT, NOT OF THE RECIPE. Around 70% is typical for a home system, 60 to 65% is normal for a first all-grain batch, and above 80% means a good crush and a patient sparge. What yours is does not much matter. Knowing it does, because every recipe you scale depends on it. The three levers, in order of effect: crush, sparge and time. A finer crush is the biggest single gain and also the fastest route to a stuck sparge, so move it one notch at a time. Sparging more slowly and a little hotter rinses more sugar out of the bed. And a mash that has not finished converting will not give up its sugar however you rinse it — an iodine test costs nothing and settles the question. One honest limit: the extract potential of a malt varies by maltster, by crop year and by moisture content. The yields here are typical published figures rather than certified ones, and if your supplier gives a number for the sack you actually bought, that one is better than this one.