Blood Alcohol Level (BAL) Calculator


Warning!!!

These calculators provide an estimate of your BAL based on population averages and they may not be able to calculate your BAL at any specific time. We do not recommend that you risk your driver's license or your life and the lives of others by using them to determine your fitness to drive a car or perform any other task.

Simple Widmark Method.


You can provide your own Widmark Constant if you like, but if you don't, we assume .75 for males and .66 for females.
The drinker
Typical woman, Widmark constant = 0.66
Typical man, Widmark constant = 0.75
Other Widmark constant
Weight in kg or in pounds (fill either blank)
The drinks
Typical Canadian beer -- 12 oz, 5 % alcohol by volume
Typical Lite beer -- 12 oz, 4 % alcohol by volume
Typical American beer -- 12 oz, 4.4 % alcohol by volume
Typical liquor, 80-proof, by the ounce-and-a-quarter shot.
Typical liquor, 80-proof, by the ounce.
Wine -- 2.5 oz, 12 % alcohol by volume
The drinking
How many drinks?
How much time in minutes between starting each drink?

to get back to this page simply click the "Back" arrow on your browser.

More complicated method.


This method is similar to the Widmark method above, but provides a more accurate estimation of body water based on weight, height and, in males, age.
The drinker
Woman Man
Weight in kg or in pounds (fill either blank)
Height in cm or else in feet and inches
For men, age in years
Estimate of alcohol metabolism rate, in mg / 100 ml blood / hour:
10 mg/100 ml blood per hour (slow)
15 mg/100 ml blood per hour (average)
20 mg/100 ml blood per hour (fast)
The drinks
Typical Canadian beer -- 12 oz, 5 % alcohol by volume
Typical Lite beer -- 12 oz, 4 % alcohol by volume
Typical American beer -- 12 oz, 4.4 % alcohol by volume
Typical liquor, 80-proof, by the ounce-and-a-quarter shot.
Typical liquor, 80-proof, by the ounce.
Wine -- 2.5 oz, 12 % alcohol by volume
The drinking
How many drinks?
How much time in minutes between starting each drink?
References and details of calculation.
Tutorial on calculating blood alcohol levels.
Acknowledgments.

Find out more about the Psychology Department at Memorial University of Newfoundland.

HMS Beagle's Web Pick of the Day, March 12-ish, 1998.

This page is http://dogsbody.psych.mun.ca/Tools/BAL/
A. Earle, 1997. (coding)
W. A. McKim, 1997. (text)