Blood Alcohol Concentration

The definition of blood alcohol content is the concentration of alcohol in one’s bloodstream, expressed as a percentage. Blood alcohol content, or BAC, is used to determine whether a person is legally intoxicated, especially under a driving while intoxicated law. In the field of traffic safety, BAC is expressed as the percentage of alcohol in deciliters of blood--for example, 0.10 percent. A 160-pound man will have a BAC of approximately 0.04 percent 1 hour after consuming two 12-ounce beers or two other standard drinks on an empty stomach. All State Laws have specific driver BAC limits, which vary by State. According to these laws, operating a vehicle while having a BAC over the given limit is illegal.

BAC CALCULATION
Fill out the form below. As information is changed, the B.A.C. reading at the bottom of the page is automatically updated.

1. NUMBER OF DRINKS:
1 2 3 4 5
2. WHAT ARE YOU DRINKING?
Reduced alc. Beer 12oz Light Beer 12oz Imported Beer 12oz Beer 12oz Malt Liquor 12oz Table Wine 5oz Champagne 5oz Fortified/dessert Wine 5oz Bloody Mary Gin and Tonic Highball Irish Coffee On the Rocks Pina Colada Screw Driver Tom Collins Whiskey Sour Margarita Airline Miniature Gimlet Old Fashioned Mint Julep Black Russian Dry Martini Manhattan Rob Roy Double On the Rocks Frozen Daiquiri
3. SELECT YOUR WEIGHT:
100 120 140 160 180 200 220 240
4. HOW LONG HAVE YOU BEEN DRINKING?
0 hours 1 hour 2 hours 3 hours 4 hours 5 hours
5. YOUR BLOOD ALCOHOL CONTENT

The basic formula for estimating a person's blood-alcohol concentration comes from The National Highway Traffic Safety Administration. Each drink in this calculation assumes a volume of of .54 ounces of alcohol (one shot of distilled spirits, a glass of wine, or 12 ounces of beer).

NOTICE: This calculator is only a reference and not absolutely accurate to be considered legal evidence. The figures you calculate are averages. Individuals may have varying results depending on their personal metabolism of alcohol. Food in your stomach may affect the rate of absorption. Factors such as medications, health and psychological conditions may also change your degree of impairment.

Disclaimer: This is in no way purported to be a guideline for how much you can drink and still drive or avoid being arrested! The best policy is don't drink & drive.

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