ABV / Brewing Calculator

Estimate a beer's alcohol content from original and final gravity. ABV, ABW, attenuation, °Plato, and calories per 12 oz. Runs locally in your browser.

Original gravity (OG)

specific gravity, before fermentation

Final gravity (FG)

specific gravity, after fermentation

Enter an OG and FG to estimate alcohol.

Specific gravity ⇄ °Plato

Convert SG → °Plato

enter a specific gravity

Convert °Plato → SG

enter degrees Plato

Alcohol by volume from the simple estimate (OG − FG) × 131.25 and the more accurate Hall formula (76.08 × (OG − FG) / (1.775 − OG)) × (FG / 0.794) — the Hall formula reads slightly higher than the linear one and is preferred for strong beers. Apparent attenuation is (OG − FG) / (OG − 1) × 100, the share of sugars the yeast consumed. °Plato (grams of extract per 100 g of wort) is converted with the standard cubic polynomial. Calories per 12 oz combine alcohol and residual (real) extract and are an estimate. Runs locally — nothing leaves your browser.