Blood Alcohol Calculator 2026 – Calculate BAC and Sobering Time
The Blood Alcohol Calculator estimates your blood alcohol content (BAC) based on drinks consumed, body weight, gender, and time elapsed. You'll also see how long it takes to become completely sober.
The calculator uses the Widmark formula, a widely used medical method for estimating BAC. Remember that the calculator provides only an approximate estimate—individual differences in metabolism can significantly affect results. Don't drive if you're unsure about your condition.
How Much Can You Drink Before Driving?
The legal BAC limit is 0.08% in most US states. One standard drink (e.g., 12 oz beer or 5 oz wine) raises BAC by about 0.02-0.03% depending on weight and gender. The body metabolizes alcohol at about 0.015% per hour. The BAC calculator helps you understand your specific situation concretely.
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Browse all tools →The blood alcohol calculator estimates blood alcohol concentration based on drinks consumed, weight, and time. An important awareness tool that helps understand alcohol's effects.
Enter drinks consumed, weight, and gender, and the calculator estimates blood alcohol concentration in per mille.
- Estimates per mille reading based on drinks consumed.
- Shows an estimate of when per mille will drop to zero.
- Accounts for the effect of gender and weight on alcohol absorption.
The per mille calculation is a rough estimate – actual effects vary individually.
- The body burns alcohol at about 0.1–0.15 per mille per hour – the rate is individual.
- Eating, medication, and fatigue affect alcohol's impact.
- The drink-driving limit is 0.05% in many countries – never drive after drinking alcohol.
The calculator is an indicative awareness tool, not a reliable gauge of driving fitness.
- Never decide your driving fitness based solely on the calculator.
- Alcohol's effect on driving ability begins even below 0.05% readings.
- The only sure way to ensure zero tolerance is not to drink before driving.