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BAC – Blood Alcohol Content Level Calculator

Use the new BAC calculator to estimate a person’s blood alcohol content when they stop drinking. It also estimates the approximate length of time until it would be 0.00, assuming they do not consume any more alcohol. This type of test calculates the percentage of alcohol in a person’s blood.

This BAC calculator works off the amount of “standard drinks” (see list below), over what amount of time was spent during a drinking episode.

One standard drink is equal to;

  • beer – 12 ounces
  • wine – 5 ounces
  • hard liquor – 1.5 ounces (shot)

Quick BAC Calculator

These results are a rough estimate based on multiple averages and not absolute.


Count the number of standard drinks consumed during the drinking episode. Enter that number in the line reading “Number of Drinks Consumed.” Then figure out the total number of hours, from the time commencing to the time stopped (to the nearest half-hour). Enter that number in the line “Number of Hours Spent Drinking.. “Hit the “Calculate” button. The results are the approximate BAC at the time of stopping. The outcome also includes the number of hours it would take to sober up to zero.

  • The legal limit for operating a motor vehicle in all 50 states is 0.08 and above.

This number is crucial because law enforcement and the courts now take DWI and DUI very seriously. In many states, the first offense can mean losing the use of a driver’s license. Some states have even more severe penalties if the person’s BAC is over a certain level.

  • The blood alcohol content is simply the amount of ethanol consumed over time. Therefore, the slower the time spent drinking and limiting the drinks rate will help insure keeping the alcohol in someone’s blood.
  • The blood alcohol content is the total percentage of alcohol grams in 100 milliliters of blood.

The human body process alcohol primarily through the liver. It starts metabolizing the ethanol immediately. It means the drinker begins detoxing from the very first sip. So, in theory, if someone drank at the same rate their body was processing it, their BAC would stay at close to zero. Many factors are affecting the rate of detoxing, including;

  • Age
  • Weight
  • Tolerance
  • Gender
  • Amount of food recently

Breathalyzer tests done in the field give instantaneous results. However, they are less accurate than blood tests done in a lab. Therefore, you may request a blood test to validate a field sobriety test.

Always drink slowly and safely.

Learn how to drink responsibly.

Learn the definition of being drunk

Read about drug tests.

Learn how long oxycontin is detectable in the body.