About Brew Math Calculators

Last updated June 9, 2026

Beer and coffee don’t share much, but they share their math: both run on ratios, and ratio mistakes compound quietly until something tastes wrong. This site collects the calculations that matter on brew day and at the grinder, with every formula printed beside its result.

On the bench

There are 6 tools: ABV Calculator, Strike Water Calculator, Priming Sugar Calculator, Brix to Gravity Calculator, Coffee Ratio Calculator, and Cold Brew Calculator. The beer side covers fermentation and packaging numbers; the coffee side covers strength ratios from pour-over to cold-brew concentrate.

Formulas, not folklore

The ABV calculator shows the (OG − FG) × 131.25 approximation it uses and notes where that shorthand drifts on big beers. The strike-water tool exposes its thermal-mass constant instead of burying it. The coffee-ratio pages state the ratio they assume — 1:15, 1:16, whatever you set — and recalculate when you change it.

Honest about precision

Brewing is a physical process measured with hobbyist instruments, so every output is an estimate and labeled as one. Homebrew responsibly and follow your local homebrewing laws. Nothing here is professional advice.

Send corrections

Brewers double-check each other’s numbers; the same is welcome here. Write to [email protected] and the page gets fixed.