Calculator
Blood Alcohol Concentration Calculator
⚠️ Medical disclaimer: This tool provides estimates only. Never drive after drinking. Results vary by individual metabolism.
Legal limit
Choose the legal driving limit for your country or region.
Legal pass/fail status uses the selected country or region threshold.
Personal profile
Set your biological profile used in Widmark estimation.
Drink entries
Add each drink with volume, ABV, and quantity.
Vol (mL)
ABV %
Qty
1
Quick presets
1h
Adjust elapsed time from first drink to reflect current Blood Alcohol Concentration estimate.
Formula: Blood Alcohol Concentration = (Alcohol(g) ÷ (Weight(kg) × 1000 × r)) × 100 − 0.015 × Hours · r = 0.68 (M) / 0.55 (F)
Frequently Asked Questions
How is Blood Alcohol Content (Blood Alcohol Concentration) calculated?
This tool uses the Widmark formula: Blood Alcohol Concentration = (Alcohol in grams) ÷ (Body weight in grams × Distribution ratio) − (Elimination rate × Hours). The distribution ratio is approximately 0.68 for men and 0.55 for women, reflecting physiological differences in body water.
Is this Blood Alcohol Concentration estimate accurate?
Results are a scientific estimate, not a definitive measurement. Actual Blood Alcohol Concentration varies with individual metabolism, food intake, hydration, medications, and other factors. Never use this tool as a basis for deciding whether to drive.
How long does it take for Blood Alcohol Concentration to reach zero?
The body eliminates approximately 0.015–0.017% Blood Alcohol Concentration per hour on average. There is no safe way to speed this up — coffee, food, and water do not reduce Blood Alcohol Concentration. The only solution is time.