How to Calculate BAC – Blood Alcohol Content

See below how to calculate BAC, or your blood alcohol content level, before you drive. All 50 states have set the minimum BAC level at 0.08% BAC for drivers over 21, 0.02% BAC for underage drivers, and 0.04% BAC for CDL drivers.

If you have been arrested for DUI because your blood alcohol content level was above the legal BAC limit, you need a top DUI attorney to fight the BAC evidence. Just because the police evidence includes the results of a DUI breath test that you think are too damaging to win your DUI case, do not plead guilty! Call a top DUI lawyer in your area right now at 844-832-6384 anytime day or night. Damaging BAC evidence can be excluded from trial!

How to calculate BAC -

The BAC calculator below shows your BAC by weight, or your estimated blood alcohol level by the number of drinks consumed in relation to your body weight. It will show you your BAC after one beer. Here is how to estimate your blood alcohol content using our drunk calculator:

1. Count your number of drinks consumed.One drink = 1 ounce of 100-proof liquor, one 5 ounce glass of table wine, or one 12 ounce bottle of regular beer.

2. Using the BAC chart below, find where “# of Drinks Consumed” and “Body Weight” intersect. This is your estimated percent of blood alcohol content.

3. Subtract from this number the percent of alcohol “burned up” during the time elapsed since your first drink. This “burn up” rate is .015% per hour. (Example: 180 lb. man – 8 drinks in 4 hours / .167% minus (.015×4) = .107 %


# of Drinks Consumed

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A high BAC at the time of your DUI arrest can look hopeless, but we can help! Even a BAC after one beer can affect your BAC by weight. Our top DUI attorneys can file motions to suppress breath test results, and we will fight your DUI charges all the way with a winnable DUI defense. A lot of drivers are stopped at DUI checkpoints and given a breathalyzer test. If you “blow” over the legal BAC limit, which is 0.08% in all 50 states, the officer will usually ask you to perform field sobriety tests. These tests are VOLUNTARY! Nothing good can come from taking them.

If you are eventually arrested for DUI, the police also may order a DUI blood test before you are taken to jail. Therefore, how to calculate BAC is important if you are unsure about your ability to drive safely. attorneys are all in, all the time. Do not plead guilty! Talk to us first. Talk to us now.