BAC Estimator
Estimate bac from your measurements.
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What this tool does
Estimate bac from your measurements. Widmark approximation; food, timing, physiology and actual ethanol amounts cause large uncertainty.
How to use the BAC Estimator
- Enter or select body weight in lb.
- Enter or select pure ethanol consumed (grams).
- Enter or select hours since drinking began.
- Enter or select widmark distribution ratio.
- Enter or select elimination rate (% bac per hour).
- Read the calculated result; change any measurement to compare alternatives.
Formula
estimated % BAC=max(0,ethanol grams/(body kg×1000×distribution ratio)×100−elimination×hours)
- weight
- Body weight (lb, before metric conversion)
- alcohol
- Pure ethanol consumed (grams)
- hours
- Hours since drinking began
- ratio
- Widmark distribution ratio
- elimination
- Elimination rate (% BAC per hour)
Widmark approximation; food, timing, physiology and actual ethanol amounts cause large uncertainty.
Worked example
For bac estimator, the following measurements illustrate the exact method: Body weight: 150; Pure ethanol consumed (grams): 28; Hours since drinking began: 2; Widmark distribution ratio: 0.68; Elimination rate (% BAC per hour): 0.015.
Inputs
- Body weight150 lb
- Pure ethanol consumed (grams)28
- Hours since drinking began2
- Widmark distribution ratio0.68
- Elimination rate (% BAC per hour)0.015
Result
- Estimated BAC (%)0.03
Results explained
- Estimated BAC (%)
- Estimated BAC (%) from the formula above. Widmark approximation; food, timing, physiology and actual ethanol amounts cause large uncertainty.
Frequently asked questions
estimated % BAC=max(0,ethanol grams/(body kg×1000×distribution ratio)×100−elimination×hours)
Widmark approximation; food, timing, physiology and actual ethanol amounts cause large uncertainty.
No. These are general-information estimates, not diagnosis, treatment, fertility advice or exercise clearance. Consult a qualified health professional.
Individual physiology, measurement technique and health conditions may cause large differences from model estimates.
No. BAC estimates never establish that driving is safe or legal; do not drive after drinking.