BAC Calculator
Estimate your blood alcohol content (BAC) based on drinks consumed, body weight, gender, and time elapsed. Includes sobering time and legal limit indicator.
⚠️ This calculator is for educational purposes only. Never drive after drinking. Results are estimates — do not use to determine if it is safe to drive.
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Frequently asked
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In the US, a standard drink contains 14 grams of pure alcohol — equivalent to 12 oz of regular beer (5% ABV), 5 oz of wine (12% ABV), or 1.5 oz of distilled spirits (40% ABV).
In the US, the legal limit is 0.08% BAC for drivers 21 and older. Many other countries use 0.05%. For commercial drivers and those under 21, stricter limits apply. Even BAC below legal limits can impair driving.
This is an estimate only, using the Widmark formula. Actual BAC varies based on metabolism, food consumption, medications, tolerance, and other factors. Never rely on a calculator to determine if you are safe to drive.