DUI / BAC Calculator

Estimate Blood Alcohol Content (BAC) for educational purposes only.

Gender

Weight (lbs)

Drinks Consumed

Beers (12oz)

Wine (5oz)

Shots (1.5oz)

Hours Since First Drink

Estimated BAC:

DISCLAIMER: This calculator provides rough estimates only. Do not rely on it to determine if it is safe to drive. Metabolism varies widely by individual. Never drink and drive.

Understanding Blood Alcohol Content (BAC)

Blood Alcohol Content (BAC) is a metric of alcohol intoxication used for legal or medical purposes. It is expressed as the weight of ethanol (in grams) per 100 milliliters of blood.

The Widmark Formula

This calculator uses the Widmark Formula, the most widely accepted method for estimating BAC over time. It accounts for gender, body weight, the amount of pure alcohol consumed, and the elapsed time since drinking began.

Gender Constant (r): Men (0.68) generally have more body water than women (0.55), which dilutes alcohol more effectively.
Metabolism Rate: On average, the human body metabolizes alcohol at a rate of 0.015% per hour.

BAC Levels and Effects

0.02% - 0.03%: Slight relaxation, mood elevation. Legal limit for commercial drivers in some areas.
0.05% - 0.06%: Impaired judgment, lowered alertness, release of inhibition. Driving is significantly impaired.
0.08%: Legal Intoxication Limit in the US/UK/Canada. Concentration, short-term memory, and speed control are impaired. Risk of crash increases exponentially.
0.10% - 0.15%: Clear deterioration of reaction time and control. Slurred speech, staggering.

"Sobering Up"

There is no way to speed up the sobering process. Coffee, cold showers, and food do not lower your BAC; only time does. The liver processes approximately one standard drink per hour. If you binge drink, you may still be over the legal limit the next morning.