Estimating BAC

You can roughly estimate the percent of alcohol in the blood by the number of drinks in relation to body weight. Please remember, this is just an estimate. Many factors such as food consumption, prior exposure to alcohol, medical issues, gender differences, and time of consumption can cause fluctuations in a person’s blood alcohol content, or BAC. The major factor in determining if you will be charged with driving under the influence will be your BAC. More information on DUI standards here. As a DC DUI lawyer will tell you, if you have doubts about whether you’re sober enough to drive, that likely means you should find alternative means of getting home.

To make an estimate:
1. Count your drinks (one drink is equal to one ounce of 100-proof liquor, one five-ounce glass of table wine, or one 12-ounce bottle of regular beer).
2. Use the following chart, and under the number of “drinks” and opposite “body weight,” find the percent of blood alcohol listed.
3. Subtract from this number the percent of alcohol “burned up” during the time elapsed since your first drink. This figure is .015 per hour. Example: 180 lb. man has eight drinks in four hours: .167 minus (.015 x 4) = .107.

This table only provides a very rough estimate of BAC. Do not use this calculation method to decide if you are sober enough to drive. The firm disclaims all liability for reliance on any of the information presented on this page. This should not be construed as legal advice or legal information. No recipients of content from this page, clients or otherwise, should act or refrain from acting on the basis of any content presented. Please drive safely and do not get behind the wheel if you have been drinking.