One question often asked in court is the determination of a particular alcohol level at the time of driving/injury or the time of the test. The standard equation used by most forensic toxicologists is the Widmark formula, developed by E.M.P. Widmark in 1932. Simply stated, the formula is a = rpc, where "a" is the quantity of alcohol in the body, "c" is the concentration of alcohol in the blood, "r" is the Widmark factor, and "p" is the body weight.

The following calculator can give the user an estimate of a possible blood alcohol level, if the drink is consumed evenly over the drinking time period, there is no substantial food in the stomach, and the drinker has an average Widmark "r" factor. Keep in mind, however, that drinking pattern, type and amount of alcohol consumed, amount of food in the stomach, physiological distress (injury,fear etc.), liver efficiency, and an equilibrium of the concentration of alchol in the body/concentration of alcohol in the blood other than a 0.68 (for men) or 0.55 (for women), will alter the blood alcohol level achieved.

DO NOT RELY ON THE CALCULATOR TO DETERMINE HOW MUCH YOU CAN CONSUME AND STILL BE UNDER YOUR STATE'S STATUTORY LIMIT. THIS CALCULATOR DOES NOT TAKE MANY IMPORTANT FACTORS INTO CONSIDERATION. YOUR ACTUAL BLOOD ALCOHOL CONCENTRATION MAY BE CONSIDERABLY DIFFERENT THAN THE CALCULATED RESULT. CONSULT A TOXICOLOGIST, WHO WILL ADDRESS ISSUES SPECIFIC TO YOUR CASE AND ADJUST THE CALCULATION.