BAC Calculator (Estimate)Math

Estimate your Blood Alcohol Content (BAC) based on gender, weight, and consumption.

Local-first

Weight (kg)

Standard drinks

1 drink = 12oz beer (5%), 5oz wine, or 1.5oz spirit

Hours since first drink

Metabolized at ~0.015% per hour

Estimated Blood Alcohol Content

0.044%

Impairment detectable. Reaction time and reflexes reduced.

Impairment Present (< 0.08% BAC)

Even with BAC under 0.08%, judgment, coordination, and reaction speed are significantly degraded. In many jurisdictions, drivers can be cited for impairment at any BAC level.

Important Safety Notice: A “standard drink” here is 14 g of alcohol (US definition). This is a rough Widmark estimate — body, food, and metabolism change real BAC. Never use it to decide if it is legal or safe to drive.

How this tool works

What it accepts, how to use it, and where your input is processed.

Show Guide

The Widmark Formula is the standard mathematical approach for estimating blood alcohol concentration. It takes into account body mass and the different rates at which men and women metabolize alcohol.

Standard Drink Definition:

One standard drink is approximately 14 grams of pure alcohol, found in 12oz of beer (5%), 5oz of wine (12%), or 1.5oz of distilled spirits (40%).

DISCLAIMER: This tool provides a mathematical estimate only. Alcohol metabolism varies greatly by individual. NEVER drink and drive. This tool is for educational purposes.

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