Blood Alcohol Content (BAC) Calculator
Estimate blood alcohol content (BAC) from drinks, body weight, sex and time using the Widmark formula. An estimate only, never a guide to whether it is safe to drive.
Formula
BAC% = (alcohol grams / (weight g × r)) × 100 − 0.015 × hours
Use it from the API
curl "https://moltcalc.com/api/calc/bac?units=metric&weight=70&sex=male&drinks=3&hours=2"
See the API docs for every endpoint and the input schema.
FAQ
Is this BAC estimate accurate enough to decide if I can drive?+
No. It is a rough Widmark-formula estimate. Real BAC varies with food, metabolism, medication, drink strength and more, so never use it to decide whether to drive. If you have been drinking, do not drive.
What counts as one standard drink?+
In the US, one standard drink contains about 14 grams of pure alcohol, roughly a 12 oz beer, a 5 oz glass of wine, or a 1.5 oz shot of spirits.
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