Method / Practical use
How to Use the Drunk Calculator
Start with your current body weight and select the biological sex used by the modified Widmark formula. Then enter either a total number of U.S. standard drinks or the serving size and alcohol by volume for each drink. Set the time since your first drink, not the time since your last one. The drunk calculator updates immediately and shows a central BAC estimate, an elimination-rate range, and an approximate time until the estimate reaches zero.
What Counts as One Standard Drink?
A U.S. standard drink contains about 14 grams, or 0.6 fluid ounces, of pure alcohol. Common examples are 12 fluid ounces of regular beer at 5% ABV, 5 fluid ounces of wine at 12% ABV, or 1.5 fluid ounces of distilled spirits at 40% ABV. These examples contain roughly the same amount of ethanol even though their total volumes are different.
Real pours often do not match those examples. A pint of strong craft beer, a large wine glass, or a cocktail with two shots may count as more than one standard drink. When the label or recipe is available, Drink Details mode is more precise because it calculates pure alcohol from servings, volume, and ABV. If those values are uncertain, the result should be treated as a wider estimate rather than an exact reading.
Why Can Actual BAC Be Different?
Blood alcohol content changes as alcohol is absorbed, distributed through body water, and eliminated. The Widmark distribution factor is a population-based shortcut; it cannot know an individual's exact body composition or total body water. Food can slow absorption, while drinking quickly can produce a higher peak. Carbonation, medications, liver health, age, recent drinking history, and inaccurate serving sizes can also change the result.
This model assumes all entered alcohol has been absorbed. That makes the estimate easier to understand, but it may overstate BAC shortly after a recent drink and miss a later rise while alcohol is still moving from the stomach and intestine into the bloodstream. Two people who enter the same weight and drinks can therefore have different measured BAC values. Use the model range as context, not as a confidence interval or personal guarantee.
How Long Until BAC Reaches Zero?
The central calculation subtracts an average elimination rate of 0.015 BAC percentage points for each hour since your first drink. The lower and upper estimates use 0.025 and 0.010 per hour to show how much the answer changes across a plausible range of elimination rates. Estimated sober time divides the current central estimate by 0.015 and rounds it into hours and minutes.
Metabolism is not a countdown that can be accelerated on demand. Coffee may make someone feel more awake, and food may affect absorption, but neither removes alcohol already circulating in the blood. Exercise, sleep, vomiting, and cold showers do not create an instant drop either. If more alcohol is consumed, the projection no longer applies and the inputs must be updated.
Drunk Calculator vs. Breathalyzer
A drunk calculator predicts BAC from information you enter. A calibrated breathalyzer samples alcohol in exhaled breath and uses that measurement to estimate blood alcohol concentration. A laboratory blood test directly measures alcohol in a blood sample. Because these methods use different evidence, a calculator cannot confirm a breath or blood result and cannot establish legal sobriety.
The safest use of this tool is planning: understanding how standard drinks add up, seeing why time matters, and arranging a sober ride before drinking. Do not wait for the gauge to cross a particular line before changing plans. Impairment can begin below the common 0.08% U.S. driving threshold, local rules vary, and a measured result may be higher than the estimate shown here.
