BAC Calculator

Estimate your Blood Alcohol Content and time to sobriety based on drinks consumed.

Gender

Body Weight

Your body weight in kilograms.

Drink Type

Number of Drinks

Standard drink units consumed.

Hours Elapsed

Time since first drink.

Coursera Plus

Unlimited access to 7,000+ world-class courses, hands-on projects, and job-ready certificate programs.

Start Learning

Current BAC

0.00%

after 1 hour since 2 beers

Peak

Peak BAC

0.00%

Sober In

Time to 0%

0 hrs

Status

Condition

Safe

BAC Over Time

Documentation

How BAC Works

Blood Alcohol Content (BAC) measures the percentage of alcohol in your bloodstream. It is influenced by your weight, gender, the type and amount of alcohol consumed, and the time elapsed since drinking.

⚠️ Important

This calculator provides estimates only. Do NOT rely on it to determine if you are safe to drive. When in doubt, don't drive.

The Widmark Formula

BAC = AW × r × 100 − (β × t)

0.00% = 28g70kg × 0.68× 100 − (0.015 × 1)

Where: A = Alcohol in grams, W = Body Weight (kg), r = Widmark Factor (0.68 for men), β = Elimination rate (0.015/hr), t = Hours elapsed.

Last Updated: February 2026

Disclaimer: This calculator provides estimates for educational purposes only. Actual BAC can vary based on many factors including food intake, medications, and individual metabolism. Never drink and drive.