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.
Reach for this calculator when you need a standardised health metric to discuss with a healthcare provider or to use as a baseline for a fitness programme. The result gives you a number that carries more meaning than subjective assessments.
Many users apply adult health classifications to children and teenagers, which is incorrect. Paediatric norms for height, weight, BMI, and body composition are age-and-sex-specific. Use age-appropriate reference tools for anyone under 18.
A nurse calculates a patient's health metric during a routine assessment, then uses the result alongside other clinical indicators to contextualise the finding — correctly treating the number as one data point among several rather than a standalone answer.
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.
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