What is a good mash efficiency for homebrewing?

Most homebrewers achieve 65–80% mash efficiency. BIAB typically yields 70–80%, batch sparging 68–76%, and fly sparging 75–85%. Efficiency above 85% is excellent but risks tannin extraction from over-sparging. Aim for consistent results rather than chasing the highest possible number — knowing your system's efficiency lets you plan accurate recipes.

What is the difference between mash efficiency and brewhouse efficiency?

Mash efficiency measures the extract collected in the kettle before the boil as a percentage of the theoretical maximum from your grain bill. Brewhouse efficiency accounts for all losses throughout the entire process — including boil-off concentration, trub loss, and transfer losses into the fermenter. Brewhouse efficiency is always lower than mash efficiency, typically by 5–10 percentage points.

How can I improve my mash efficiency?

The most impactful improvements are: a finer grain crush (without producing excessive flour), maintaining mash temperature (65–68°C for standard ales), hitting the correct mash pH (5.2–5.4), mashing for 60–90 minutes, and thorough sparging. Poorly crushed grain is the most common cause of low efficiency.

Why do higher-gravity recipes have lower efficiency?

In very high-gravity mashes, the wort becomes more concentrated and viscous, which reduces the diffusion of sugars from the grain husk. Additionally, the sparge rinses less efficiently at higher concentrations. This is normal — many brewers plan for 2–5% lower efficiency on big beers and compensate with more grain.

What does PPG (points per pound per gallon) mean?

PPG is a measure of the maximum extract a grain can contribute to one US gallon of wort per pound of grain under ideal conditions. Pale malt typically has a PPG of 36–37. Roasted malts with less fermentable starch have lower PPG values, around 25–30. Your actual extract will always be lower than the theoretical maximum — that gap is what efficiency measures.

Mash Efficiency Calculator — Mash & Brewhouse Efficiency

Measure how well your mash extracted fermentable sugars from the grain and calculate true brewhouse efficiency.

Grain Weight

Total weight of all grains in your mash — weigh your full grain bill before milling

Pre-Boil Gravity

Specific gravity of the wort collected in the kettle before the boil begins — stir well and measure at a consistent temperature

Pre-Boil Volume

Volume of wort in the kettle before the boil — measure at the kettle, not the mash tun

Grain Potential (PPG)

Select your base malt type or choose Custom to enter your own PPG value — use the average PPG for a mixed grain bill

Mash System

Your brewing system — affects typical efficiency range expectations but not the calculation itself

Post-boil values (for brewhouse efficiency)

Post-Boil Gravity

Original gravity of the wort after the boil — your OG measurement before pitching yeast

Post-Boil Volume

Volume of wort in the kettle after the boil, before transferring to the fermenter

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.