Homebrewing calculators
Gravity, alcohol, bitterness, mashing and carbonation — each one showing the formula it used and citing where that formula comes from, so you can check the answer instead of trusting it.
Gravity & Alcohol
- ABV CalculatorAlcohol by volume from original and final gravity, with both the standard and the high-gravity formula side by side, plus Brix and Plato input.
- Brix to Specific Gravity ConverterConvert between Brix, degrees Plato and specific gravity in both directions, using the published conversion polynomials, with a reference table.
- Attenuation CalculatorApparent attenuation from original and final gravity: how much of the sugar your yeast actually ate, and what typical strains reach.
- Gravity Dilution CalculatorWater to add to hit a target gravity, the gravity after dilution, and the result of blending two volumes, by mass balance on gravity points.
- Hydrometer Temperature Correction CalculatorCorrected specific gravity from a hydrometer reading taken above its 60°F/60°F calibration point, from a hydrometer manufacturer's own published table.
Hops & Bitterness
Mashing & Water
Packaging & Carbonation
- Priming Sugar CalculatorBottle conditioning sugar from target carbonation and beer temperature, for corn sugar, table sugar or DME, with CO2 targets by style.
- Keg Carbonation CalculatorCO2 regulator pressure for a target carbonation level at your keg's temperature, from the CO2 solubility physics behind the published ASBC table.
Where the numbers come from
Brewing calculators disagree with each other more than you would expect, because several of the formulas in common use are empirical fits rather than derivations, and different tools quietly pick different ones. The ABV pages here show two formulas side by side for exactly that reason — at ordinary strengths they agree, and at high gravity they part by nearly a percent.
Where a formula's source could not be retrieved, the calculator is simply not here — that is why there's no refractometer post-fermentation correction yet. Rager bitterness, strike water and mash infusion, hydrometer correction and keg carbonation were all in that position too, until a fetchable source turned up for each. Each page says which sources it used and when they were retrieved.