The BAC (Blood Alcohol Content) calculator estimates your blood alcohol level based on the drinks you've consumed, your body weight, gender, and hours since drinking. Use it to better understand how alcohol affects your body — and make safer decisions about driving and activity after drinking.
BAC is expressed as grams of alcohol per 100mL of blood. The Widmark formula calculates BAC from drinks consumed, body weight, gender factor, and hours elapsed. The body metabolizes approximately 0.015% BAC per hour regardless of coffee, food, or activity.
⚠️ Important: This calculator is for educational purposes only. Never rely on any calculation to determine fitness to drive. Even a BAC below the legal limit impairs reaction time and judgment.
US: 0.08%. UK: 0.08% England/Wales, 0.05% Scotland. EU most countries: 0.05%. Always check your jurisdiction. Commercial drivers and new drivers often have stricter limits.
BAC drops ~0.015% per hour. At 0.08% BAC, it takes about 5–6 hours to fully clear. At 0.16%, over 10 hours. Sleep does not speed up elimination.