Understanding Blood Alcohol Concentration (BAC)
Blood Alcohol Concentration (BAC) is the primary metric used to measure the amount of alcohol in your bloodstream. When you use a BAC calculator, you're looking at a percentage: a BAC of 0.10% means that 0.10% of your total blood is pure alcohol.
While the legal limit for driving in most states is 0.08%, impairment begins much earlier. Even at 0.02% or 0.05%, your coordination, reaction time, and judgment are already starting to slip.
The Science Behind This Calculator
This tool utilizes the Widmark Formula, the industry-standard algorithm used by forensic scientists and medical professionals to estimate intoxication levels. Unlike simple estimates, our calculator accounts for the absorption curve—meaning it factors in the time it takes for alcohol to actually enter your bloodstream after your first sip.
For more information on how BAC works, see our article on What is a BAC calculator?
What Is a "Standard Drink"?
Most people screw up their BAC estimates because they don't realize how much they're actually drinking. A standard drink is 14 grams of pure alcohol, but a craft IPA or heavy-handed margarita is actually two or three drinks if not more.
| Drink Type | Volume | ABV |
|---|---|---|
| Light Lager | 12 oz | 4.2% |
| Regular Beer / Seltzer | 12 oz | 5% |
| IPA / Craft Beer | 12 oz | 6% - 9% |
| Wine | 5 oz | 11% - 14% |
| Hard Liquor | 1.5 oz | 40%+ |
How Much Alcohol Is In Your Drink?
Not all drinks are created equal. Here's what's actually in your drink:
How Long Does Being Drunk Last?
Black coffee, cold showers, greasy food? None of them sober you up. Sure, you might feel more alert, but your BAC doesn't change. The only thing that lowers your BAC is time.
Want to know how long it takes to sober up?
Read: How long does being drunk last?
What Happens If You Get a DUI?
A DUI will mess up your life. You lose your license, pay thousands in fines, and might do jail time. And even if you feel fine, alcohol stays in your system way longer than you think.
Figure out your ride home before you start drinking, not after.