BAC Calculator
Estimate your Blood Alcohol Content (BAC) based on drinks consumed and body weight.
Biological Sex
Units
Body Details
Consumption
1 Standard Drink = 12oz Beer, 5oz Wine, or 1.5oz Liquor.
How many hours have passed since you started drinking?
Understanding Blood Alcohol Content (BAC)
BAC measures the percentage of alcohol in your blood. A BAC of 0.10% means that there is 0.10 gram of alcohol for every 100 milliliters of blood.
The Widmark Formula
This calculator uses the Widmark Formula:
BAC = [Alcohol Consumed (grams) / (Body Weight (grams) x r)] x 100
- r (Widmark Factor): For men, this is approximately 0.68. For women, it is approximately 0.55. This difference exists because women generally have a higher percentage of body fat and lower body water content than men.
- Elimination Rate: The average human liver processes alcohol at a rate of roughly 0.015% per hour.
Legal Limits & Impairment
- 0.00%: Sober.
- 0.02% - 0.05%: Mild impairment, slight relaxation.
- 0.05% - 0.08%: Noticeable impairment, reduced coordination.
- 0.08% (US Limit): Illegal to drive in all 50 states.
- 0.10% - 0.15%: Significant impairment, slurred speech.
- 0.20%+: Severe intoxication, blackout risk.