BAC Calculator

Estimate your Blood Alcohol Content (BAC) based on what you've had to drink

This calculator estimates your Blood Alcohol Content (BAC) using the Widmark formula. It takes into account your gender, weight, alcohol consumed, and time elapsed.

Calculator Inputs

Gender*

MaleFemale

Body Weight*

Standard Drinks Consumed*

1 drink = 12oz beer, 5oz wine, or 1.5oz spirits

Time Since First Drink (Hours)*

Results

Enter values above to see your results

How It Works

Alcohol is distributed in body water. Since men and women have different water ratios (approx 0.68 vs 0.55), gender affects BAC. The body metabolizes alcohol at a rate of approximately 0.015% per hour.

Tips & Best Practices

•Food in the stomach slows absorption but does not reduce the total alcohol consumed.
•This is ONLY an estimate. Do not use this to justify driving.
•Legal limit in many places is 0.08%, but impairment starts much earlier.

Frequently Asked Questions

What is a standard drink?

A standard drink contains about 14 grams of pure alcohol. This is roughly 12oz of 5% beer, 5oz of 12% wine, or 1.5oz of 40% spirits.

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