Blood Alcohol Content (BAC) Calculator

Determine Your Tolerance BAC Results
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Metabolic rate:
Elapsed time: hrs    min
Total Alcohol Consumed
Percent alcohol: %
Total servings:
Alcohol History
    [no alcohol added]

    Blood Alcohol Concentration (BAC)

    Blood Alcohol content is measured by the amount of ethanol (aka – alcohol) that is present in one’s bloodstream. The Federal legal limit for operating a vehicle requires that you be under .08 to legally drive. However, it should be noted that impaired driving typically begins to occur between .05 – .08. To help put this into perspective, The National Transportation Safety Board reported that Europe saw the number of traffic deaths caused by drunk drivers reduced by more than half since lowering their nations legal limit to .05.

    .00% - .03%NormalNone
    .031% - .06%>Mild euphoria
    >Increased confidence
    >Decreased inhibition

    .061% - .09%>Dis-inhibition>Impaired Judgement
    >Impaired fine-muscle control
    .10% - .19%>Anger / Depression
    >Mood swings
    >Decreased libido
    >Impaired Reaction Times
    >Motor Control
    >Slurred Speech
    >Possibility of Nausea
    .20% - .30%>Impaired sensations
    >Possibility of falling unconscious
    >Severe motor impairment
    >Loss of consciousness
    >Memory blackout
    .31% And UP>Not aware of surroundings

    >Possibility of Alcohol Poisoning
    >Heart Rate
    >Possibility of going into a Coma
    >Possibility of death

    What Affects Your BAC?

    • Tolerance
    • Gender
    • How fast you have been drinking.
    • How much alcohol you’ve ingested.
    • Weight / Body size
    • Food in Stomach
    • Medication

    Calculate Your BAC On The Go!

    While it’s true, this is one of the most flexible BAC calculators on the web – It’s probably not the most mobile friendly. Here are just a few great apps to help you keep yourself out of trouble on the go.

    About The BAC Calculator

    The formula for this calculator was derived using a variation of the standard widmark formula:


    There are a lot of variables going on here – so Let’s break down each one…

    EBACEstimated Blood Alcohol Content
    AIs the amount of actual alcohol per serving in your drink. The easiest way to get this number is to multiply the amount of fluid ounces by the % of alcohol it contains.
    • Beer: 12 oz @ 5% (.60 oz of alcohol per serving )
    • Wine: 5 oz @ 12% (.60 oz of alcohol per serving )
    • Liquor: 1.5 oz @ 40% (.60 oz of alcohol per serving )
    n# of drinks consumed.
    5.14Is our Conversion factor Constant. ( .823 x 100/16 ) Where .823 is used to converted liquid oz to weight. While the value of 100 is used to convert that number to a percent and then finally 16 is used to convert from pounds to ounces.
    Wbody weight in lbs
    rThis variable represents the average rate at which alcohol can be processed by the body. Since these numbers can and will vary from person to person - we use the average for our calculations ( .73=men / .66=women).
    HHours drinking

    Alright, Now that we’ve defined our variables – It’s just a simple matter of plugging in our own information to figure out our intoxication level:


    1.)  A 200 lbs man drinking 4 beers in 2 hours

    •  (.6 x 4) x 5.14 ) / ( 200 *.73 ) – ( .015* 2 )
    • After calculations… ( 12.336/  146 ) – ( .03) = .054 BAC


    The Disclaimer:It should be noted that while this formula has been the standard for calculating intoxication levels for nearly a century – some of the variables will differ slightly from person to person. As such, with any BAC calculator – It is recommended that you only use these calculations as a rough estimate!


    Straight 2 The Pint