Blood Alcohol Calculator - Estimated BAC % (Widmark)
Free online blood alcohol concentration (BAC) calculator. Estimate blood alcohol levels and hours to sobriety using the Widmark formula.
Inputs
🔒 Local ProcessingHow to Use This Calculator
- Enter body weight, number of standard drinks, and hours since first drink.
Formula & Mathematical Method
Widmark scientific equation modeling ethanol body water distribution and metabolic elimination.
BAC = [ Alcohol(g) / (r × Weight(kg) × 10) ] - (0.015 × Hours)Explanation of Variables
| Symbol | Variable Name | Description & Role in Calculation |
|---|---|---|
| r | Widmark Factor | Gender body water ratio (0.68 male, 0.55 female). |
Worked Calculation Examples
75kg Male 3 Drinks over 2 Hours
Scenario: Social drinking.
Interpretation of Results
Health and metabolic metrics are calculated using validated empirical equations (such as Mifflin-St Jeor, Devine, or Boer formulations). Results provide statistical estimates of physiological parameters for general wellness planning.
Estimated Physiological Value
Your calculated metabolic or anthropometric metric based on standard demographic averages.
Key Context: Use this figure as an informational baseline for nutritional or fitness goal setting.
Practical Use Cases
Nutritional and Fitness Program Design
Establish structured dietary intake targets, hydration goals, or training heart rate zones.
Long-Term Wellness Progress Tracking
Monitor changes in body composition, cardiovascular recovery, or metabolic requirements over time.
Limitations & Key Assumptions
- Formulas are derived from population-level clinical studies and cannot account for unique genetic, endocrine, or pharmacological differences.
- Hydration, body fat, and calorie needs fluctuate with daily temperature, humidity, stress, and hormonal cycles.
- Calculations are informational estimates and are NOT medical diagnoses, clinical evaluations, or therapeutic advice. Consult a qualified healthcare professional.