Alcohol Dilution Calculator

Calculate how much water to add to reduce a spirit or wine to a target ABV. Works for any volume and starting strength.

Current volume (ml)

Current ABV (%)

Target ABV (%)

Dilutant

About Alcohol Dilution Calculator

Uses the Pearce equation: V₁ × C₁ = V₂ × C₂ (volume × concentration = constant). Pure alcohol (ethanol) has a density slightly less than water, so mixing causes slight volume contraction — this tool uses the simplified linear model (accurate within ~2% for ABV below 60%). Useful for homebrewing, cocktail batching, and reducing cask-strength spirits to bottling strength.