About Brew Math Calculators

Last updated June 5, 2026

I brew beer and over-think my coffee. These are the ABV, carbonation, strike-water, and brew-ratio calculators I actually use on brew day — with the formulas (and their assumptions) shown in full.

What’s on this site

Right now there are 6 calculators here: ABV Calculator, Strike Water Calculator, Priming Sugar Calculator, Brix to Gravity Calculator, Coffee Ratio Calculator, and Cold Brew Calculator. Each one is a single-purpose tool that shows its formula, lists its assumptions, and runs on any device with no signup.

Why these are different

Most calculator sites hand you a number and hide the formula. Every tool here does the opposite: the exact formula, the assumptions, and a worked example are shown right on the page, so you can check the result instead of trusting it blindly. There’s no account, no paywall, and no signup.

How the math is kept honest

Each formula is shown in full and was independently re-derived and spot-checked against the calculator’s code. Reference values (typical rates, averages, rules of thumb) are labeled as approximate and are editable, so you can put in your own real numbers. Homebrew responsibly and follow your local homebrewing laws. Nothing here is professional advice.

Found a mistake?

I’d genuinely like to know. Email [email protected] and I’ll fix it.