Blood Alcohol Concentration (BAC) Estimate
BAC = (drinks × 0.6) / (weight × Widmark factor) − (0.015 × hours). NHTSA Widmark formula.
Result
Estimated BAC
0.070%
⚠ Impaired (some states .05 limit). ~4.7 hr to reach 0.
- Drinks3
- Weight (lb)160
- SexMale
- Hours elapsed1
- Raw BAC0.0700%
- Adjusted BAC0.0700%
- Tier⚠ Impaired (some states .05 limit)
- Hours to zero4.7
Step-by-step
- Pure alcohol oz = 3 × 0.6 = 1.80 oz.
- BAC = (1.80 × 5.14 / (160 × 0.68)) − (0.015 × 1).
- = 0.0700% (negative truncated to 0).
How to use this calculator
- Enter standard drinks, weight, sex, hours.
- Output is estimate only; NEVER drive within 1-2 hr of any drinking.
About this calculator
Widmark BAC formula: rough approximation. Actual BAC depends on food in stomach, hydration, drink rate, individual metabolism, and alcohol type. Liver clears ~0.015% BAC per hour (one drink). US legal driving limit: 0.08% (some states 0.05%). Never trust this calc as legal predictor — devices vary, your tolerance varies. Source: NHTSA Widmark equation; CDC.
Frequently asked
Population average ±20-30%. Individual variation large. Use breathalyzer for actual measurement.
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