Homebrew beer recipe calculator
Free client-side Homebrew beer recipe calculator web utility.
Alcohol by Volume & Attenuation
Hop Bitterness (Tinseth Model)
Beer Color (Morey Model)
Hydrometer Temperature Correction
Priming Sugar for Bottle Conditioning
About this tool
How to use it
- Enter your Original Gravity (OG) and Final Gravity (FG) to calculate real Alcohol by Volume (ABV) and attenuation percentage.
- Calculate hop bitterness (IBUs) using hop alpha acid %, weight, boil time, and the standard Tinseth utilization model.
- Estimate beer color (SRM and EBC) based on grain bill malt pounds and wort volume with live color swatches.
- Calculate hydrometer temperature corrections and exact priming sugar weights for bottle conditioning.
Why it matters
Precision in brewing separates mediocre beer from medal-winning craft brews. Standard hydrometer readings shift with temperature, attenuation dictates yeast health, and accurate hopping ensures proper malt-to-bitterness balance (BU:GU ratio).
When to use it
Use this calculator on brew day during mashing and boiling, when taking fermentation gravity readings, and prior to bottling or kegging your homebrew batch.
Common questions
What is the standard formula for ABV?
The classic formula is ABV = (OG - FG) * 131.25. For high-gravity beers (above 1.070 OG), an advanced non-linear formula accounts for density changes in concentrated wort.
What is the BU:GU ratio?
The Bitterness Units to Gravity Units (BU:GU) ratio measures perceived bitterness balance. A ratio of 0.8-1.0 denotes a hop-forward beer (like an IPA), while 0.3-0.5 indicates a malt-accented beer (like a Brown Ale or Munich Dunkel).
Why do hydrometer readings need temperature correction?
Hydrometers are calibrated to measure liquid density at a specific calibration temperature (usually 60°F / 15.5°C or 68°F / 20°C). Warmer wort is less dense, causing uncorrected hydrometers to read artificially low.