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BAC Calculator
About the BAC Calculator
Estimate blood alcohol concentration. It is only an estimate, and you should never use it to decide whether it is safe to drive.
How to use the BAC Calculator
- Enter the number of Standard Drinks, your Body Weight (kg) and the Time Since First Drink (Hrs).
- Choose the Alcohol Meta-Rate (slow, average or fast).
- Press Calculate Impairment.
Formula and method
The estimate uses the Widmark formula: alcohol consumed divided by body weight and a body-water factor, minus the amount burned off over time (about 0.015 per hour).
Tips
- Never drive after drinking. Real BAC depends on food, medication, sex, genetics and health.
Frequently Asked Questions
No. Results are rough estimates. The only safe choice is not to drive after drinking.