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Calculate water addition to dilute spirits to target proof or ABV. Barrel-proof bottling and proofing calculator for distillers.
Calculate blend ratios to achieve target ABV from liquids of different alcohol concentrations. Wine, spirits, and cocktail blending math.
Calculate number of bottles from batch volume for wine, beer, and spirits. Standard 750ml, 375ml, and 1L bottle yields with loss allowance.
Evaporation rate depends on climate, barrel size, and warehouse conditions. Smaller barrels have higher surface-to-volume ratio and faster loss.
Annual loss = 2–4% (Scotland/humid) | 4–10% (Kentucky/dry)Loss compounds annually on remaining volume. 10% annual loss for 4 years: 0.9^4 = 66% remaining (34% total loss).
Remaining = Initial × (1 − Rate)^YearsIn dry warehouses (Kentucky), proof increases 1–3 degrees per year. Humid climates (Scotland) may decrease proof as alcohol evaporates preferentially.
Proof rises as water evaporates faster than ethanol (in dry climates)Updated: July 2026
Initial 53 gal, 5% annual loss: 53 × 0.95^4 = 43.3 gal remaining. Proof rises from 125 to ~130 entry proof.
Higher surface ratio: 8% annual loss. 15 gal × 0.92^2 = 12.7 gal. Faster extraction, faster evaporation.
2% annual loss in humid dunnage warehouse: 200L × 0.98^12 = 157L. Proof may drop 2–4 degrees over 12 years.
Barrel aging loses volume to evaporation (angel's share) and absorption into wood. Enter initial fill volume, barrel size, aging duration, and climate to estimate remaining volume, proof change, and final bottle yield.