Hydrometer Calculator 2026
Calculate ABV, specific gravity, and attenuation for your homebrew, wine, or spirits. Enter your original and final gravity readings to get instant results.
Gravity Readings
Enter your hydrometer measurements to calculate alcohol content
The specific gravity reading taken before fermentation begins.
The specific gravity reading taken after fermentation is complete.
Your Brewing Results
Alcohol content, attenuation, and fermentation analysis
Enter your original and final gravity readings above and click Calculate ABV & More to reveal your brewing results.
Common Hydrometer Readings
Typical original gravity ranges for different types of fermented beverages. Use this as a guide when planning your brews.
| Beverage Type | OG Range | FG Range | Typical ABV |
|---|---|---|---|
| Light Lager | 1.032 – 1.040 | 1.006 – 1.012 | 3.5% – 4.5% |
| Standard Ale | 1.045 – 1.055 | 1.010 – 1.015 | 4.5% – 6.0% |
| IPA | 1.056 – 1.070 | 1.010 – 1.018 | 6.0% – 7.5% |
| Stout | 1.050 – 1.075 | 1.012 – 1.020 | 5.0% – 8.0% |
| Belgian Strong | 1.075 – 1.110 | 1.012 – 1.024 | 8.0% – 12.0% |
| Red Wine | 1.070 – 1.100 | 0.990 – 1.000 | 11.0% – 14.5% |
| White Wine | 1.065 – 1.095 | 0.990 – 0.998 | 10.0% – 13.5% |
| Mead (Traditional) | 1.075 – 1.110 | 0.996 – 1.010 | 8.0% – 14.0% |
| Cider | 1.045 – 1.065 | 0.995 – 1.005 | 5.0% – 7.5% |
| Saison | 1.048 – 1.065 | 1.002 – 1.010 | 5.5% – 8.0% |
Hydrometer Calculator FAQ
Everything you need to know about using a hydrometer, calculating ABV, and understanding your fermentation results.
A hydrometer is a calibrated glass instrument used to measure the specific gravity (density) of liquids relative to water. It works on the principle of buoyancy—the denser the liquid (more dissolved sugars), the higher the hydrometer floats. Brewers and winemakers use it to track sugar content and calculate alcohol production during fermentation.
ABV (Alcohol By Volume) is calculated using the formula: ABV = (Original Gravity – Final Gravity) × 131.25. For example, if your OG is 1.050 and FG is 1.010, the calculation is (1.050 – 1.010) × 131.25 = 5.25% ABV. This calculator automates this process for you.
Original Gravity (OG) is the specific gravity reading taken before fermentation begins, representing the total sugar content in your wort or must. Final Gravity (FG) is the reading taken after fermentation is complete, when yeast has converted sugars to alcohol. The difference between these readings indicates how much sugar was fermented.
Apparent attenuation is the percentage of sugars that yeast has fermented into alcohol and CO2. It’s calculated as: ((OG – FG) / (OG – 1)) × 100. Most ale yeasts attenuate between 65-75%, while lager yeasts typically attenuate 70-80%. Higher attenuation means a drier, less sweet final product.
Take the Original Gravity reading just before pitching yeast, after cooling your wort. For Final Gravity, wait until fermentation appears complete (no bubbles in airlock for 2-3 days) and take a reading. Wait 2-3 more days and take another reading—if both readings are identical, fermentation is complete.
A properly calibrated hydrometer should read exactly 1.000 in pure water at the temperature specified on the hydrometer (usually 20°C/68°F or 15.5°C/60°F). If it reads differently, you’ll need to apply a correction factor to all your readings. Temperature also affects readings—most hydrometers include a temperature correction chart.