Time to Sober Up Calculator

It first estimates your peak blood alcohol concentration (BAC) with the Widmark equation, BAC = (ounces of pure alcohol times 5.14) divided by (body weight in pounds times r), where r is 0.68 for men and 0.55 for women. It then subtracts a steady elimination rate of 0.015 percent BAC per hour to project when your level reaches 0.08 and 0.00. The time until sober is your current BAC divided by 0.015.

One US standard drink contains about 0.6 fluid ounces (14 grams) of pure alcohol. That is roughly a 12 oz beer at 5 percent, a 5 oz glass of wine at 12 percent, or a 1.5 oz shot at 40 percent. Enter the total number of standard drinks you had, using fractions such as 2.5 for partial drinks.

No. This is an educational estimate only, and individual results vary widely. Impairment can remain even when your BAC is below 0.08, and the only truly safe blood alcohol level for driving is 0.00. If you have been drinking, do not drive.

Your body clears alcohol at a roughly fixed rate of about 0.015 percent BAC per hour, and nothing speeds it up. Coffee, cold showers, food, water, and exercise do not change the rate, only time does. For example, a BAC of 0.15 takes about 10 hours to reach 0.00, since 0.15 divided by 0.015 is 10.

No. The Widmark model assumes alcohol is fully absorbed and ignores food, hydration, medications, age, illness, and individual differences in body water and liver enzymes. Real elimination rates range from about 0.010 to 0.020 percent per hour, so treat the result as a rough guide rather than a precise prediction.

No. This calculator is for general education and is not a substitute for professional medical advice. If you are worried about alcohol use, or if someone shows signs of alcohol poisoning such as confusion, vomiting, or slowed breathing, seek emergency help right away.