BAC Calculator

Estimate Blood Alcohol Content (BAC) — for educational use only

Body Weight

Unit

Hours since drinking started

Drinks consumed

⚠ This is an estimate only. Never drink and drive. US legal limit is 0.08% BAC. Many factors affect actual BAC. Do not rely on this for driving decisions.

About

Uses the Widmark formula: BAC = (grams of alcohol / (body weight × r)) × 100, minus 0.015% per hour of metabolism. r = 0.68 for males, 0.55 for females (body water distribution factor).