Your blood alcohol content, estimated.
Enter what you drank, your weight, sex and the time since your first drink. The Widmark formula estimates your current BAC, how impaired you likely are, and how long until your body clears the alcohol completely.
Your drinks and body
One standard drink = 12 oz beer, 5 oz wine, or 1.5 oz spirits.
Your body weight in pounds.
Biological sex affects alcohol metabolism rate.
Time elapsed since your first drink.
Widmark formula: BAC = alcohol grams / (body weight in grams x r), minus 0.015% per hour. r = 0.68 for men, 0.55 for women. One standard drink = 14 g of alcohol. Results update as you type.
What your BAC means
How your BAC falls over time
BAC milestones
Effects by BAC level
Typical effects at each level. The highlighted row is the closest to your estimated BAC.
| BAC | Status | Typical effects |
|---|
Blood alcohol content, explained
What is Blood Alcohol Content?
Blood Alcohol Content (BAC) measures the percentage of alcohol in your bloodstream. A BAC of 0.08% means 0.08 grams of alcohol per 100 milliliters of blood. In all 50 US states, a BAC of 0.08% or higher is legally impaired for driving. Effects begin at much lower levels.
How BAC is Calculated
BAC is estimated using the Widmark formula: BAC = (alcohol consumed in grams / (body weight in grams × gender constant)) - (metabolism rate × hours). The gender constant is 0.68 for men and 0.55 for women. The body metabolizes approximately 0.015% BAC per hour regardless of body size.
BAC Levels and Their Effects
At 0.02-0.03% BAC, you may feel slightly relaxed. At 0.05-0.06%, judgment and inhibitions are reduced. At 0.08%, legal impairment begins with poor coordination and reaction time. At 0.15%, significant impairment occurs. At 0.30%+, there is risk of loss of consciousness. At 0.40%+, there is risk of death.
Factors Affecting BAC
Beyond weight and sex, BAC is affected by food in the stomach (food slows absorption), rate of drinking (faster drinking = higher peak BAC), medication interactions, fatigue, hydration level, and individual metabolic differences. This calculator provides estimates, actual BAC may vary.
Common questions
How long does it take to sober up?
Your body metabolizes alcohol at a relatively constant rate of about 0.015% BAC per hour. If your BAC is 0.08%, it will take approximately 5.3 hours to reach 0.00%. No amount of coffee, water, or food can speed up this process. Only time reduces BAC.
What is a standard drink?
A standard drink contains about 14 grams of pure alcohol. This equals 12 ounces of regular beer (5% alcohol), 5 ounces of wine (12% alcohol), or 1.5 ounces of distilled spirits (40% alcohol). Craft beers, strong wines, and mixed drinks may contain more than one standard drink.
Why do women reach higher BAC than men?
Women generally have a higher BAC than men after drinking the same amount because women have a higher proportion of body fat and lower proportion of body water. Since alcohol is water-soluble, it becomes more concentrated in women's bodies. Women also produce less alcohol dehydrogenase enzyme.
Is this calculator legally reliable?
No, this calculator provides estimates for educational purposes only. Actual BAC depends on many individual factors that cannot be accounted for in a formula. Never use this calculator to determine whether it is safe to drive. If you have consumed any alcohol, use a ride service or designated driver.
Does eating food reduce BAC?
Eating before or while drinking slows the absorption of alcohol, resulting in a lower peak BAC. However, food does not reduce BAC once alcohol is already in your bloodstream. The same total amount of alcohol will eventually be absorbed, food just slows the process.
Never drive after drinking. Not even one drink. This calculator is an educational estimate, not a measurement: your real BAC depends on food, medication, fatigue, hydration and individual metabolism, and can be far higher than the number shown here. No result on this page ever means it is safe to drive or operate machinery. If you have consumed any alcohol at all, use a ride service, public transport or a designated driver. Only time lowers BAC: coffee, cold showers and food do not. If someone is unconscious or unresponsive after drinking, call emergency services immediately.