BAC Calculator
Estimate blood alcohol content from drinks, weight, and time.
Estimated BAC
0.047%
Mild impairment
Hours to 0.000
3.1
US driving limit
0.08% (0.05% in Utah)
Widmark estimate for education only — food, medications, and metabolism vary widely. Never use this to decide whether to drive.
The Widmark model
BAC estimates alcohol grams distributed through body water (about 68% of weight for men, 55% for women), minus elimination at ~0.015% per hour. A 'standard drink' — 12 oz beer, 5 oz wine, 1.5 oz spirits — carries 14 grams of alcohol.
Why estimates mislead
Food slows absorption, carbonation speeds it, medications interact, and individual elimination ranges 0.010–0.025%/hour. Impairment begins well below legal limits — reaction time measurably degrades from 0.02%. The only safe driving BAC is zero.
Frequently asked questions
- How does the BAC Calculator work?
- Estimate blood alcohol content from drinks, weight, and time.
- Is the BAC Calculator free to use?
- Yes. The BAC Calculator is completely free, runs entirely in your browser, and requires no account or sign-up. Your inputs never leave your device.
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