Homebrewing Calculators
The brew-day maths, done for you — work out your beer's ABV, bitterness (IBU) and priming sugar, convert between Brix and gravity, correct a hydrometer or refractometer reading, hit your mash temperature with the right strike water, and dilute a too-strong wort. Established brewing formulas, cited to their sources, running entirely in your browser.
- ABV Calculator Enter your original and final gravity to get the ABV
- IBU Calculator (Tinseth) Add your hop additions
- Priming Sugar Calculator Enter your target carbonation, beer temperature, batch volume and sugar type to get the priming sugar to add at bottling.
- Brix to Specific Gravity Converter Enter a Brix or specific-gravity value to convert between the two
- Hydrometer Temperature Correction Enter your hydrometer reading, the sample temperature and the hydrometer's calibration temperature to get the corrected gravity.
- Strike Water Temperature Calculator Enter your target mash temperature, grain temperature and water-to-grain ratio to get the strike water temperature.
- Gravity Dilution Calculator Enter your current volume and gravity and a target gravity to see how much water to add.
- Refractometer Final Gravity Calculator Enter the original Brix, the current Brix reading and your correction factor to estimate the true final gravity and ABV.
- Keg Carbonation Pressure Calculator Enter your beer's temperature and target CO₂ volumes to get the regulator pressure for force carbonation.
- Beer Color Calculator (SRM & EBC) Add your malts and batch volume to estimate the beer's colour in SRM and EBC, with a visual swatch.
- Mash Efficiency Calculator Enter your measured OG, grain weight and batch volume to see your mash efficiency percentage.
- Yeast Pitching Rate Calculator Enter your batch size, original gravity and pitch rate to see the yeast cells needed
From mash to bottle, the numbers that matter
Brewing is equal parts craft and measurement, and a handful of numbers run through the whole day. Before the boil, the strike-water calculator gets your mash to the right temperature and the Brix↔SG converter squares your refractometer with your hydrometer. During the boil, the IBU calculator balances the bitterness of your hop additions using Glenn Tinseth's model. And when a reading looks off, the temperature correction and refractometer tools set it straight.
After fermentation, the ABV calculator turns your original and final gravity into alcohol content (with the accurate formula for big beers), and at bottling the priming-sugar calculator doses exactly the carbonation you want — no bottle bombs. If a batch comes out stronger than planned, the dilution calculator tells you how much water to add. Every formula is the established one and cited to its source; nothing is uploaded, and it all works offline in the brewhouse. For unit conversions and general maths, see the Units and Calculators categories.
Frequently asked questions
Are these homebrewing calculators accurate?
They use the established brewing formulas — ABV = (OG − FG) × 131.25 (and Hall's equation for strong beers), the Tinseth IBU model, the standard Brix↔SG cubics, hydrometer temperature correction, priming-sugar from CO₂ stoichiometry, Palmer's strike-water equation, and Sean Terrill's refractometer cubic. Each was verified against its source (Palmer, Tinseth, Terrill, Brewer's Friend) and is cited on the tool.
Do the tools work in metric and imperial?
Yes where it matters — the strike-water and priming tools take °C or °F, and the strike tool handles L/kg or qt/lb. Gravity is unitless specific gravity; IBU and priming volumes are metric (litres), which you can convert in the Units category.
Is anything uploaded?
No. Every tool runs entirely in your browser — no accounts, no uploads, nothing sent to a server. Your recipe numbers stay on your device, and the tools work offline on brew day.
Are these estimates or exact?
The gravity, ABV, Brix and strike-water maths are exact formulas. IBU, priming sugar and refractometer correction are industry-standard models that estimate real-world behaviour — excellent for designing and comparing recipes, but hop utilization and refractometer factors vary, so treat those as close estimates and confirm critical readings with a hydrometer.