Health
Blood Alcohol (BAC) Calculator
Estimate blood alcohol concentration using the Widmark formula.
Inputs
Blood Alcohol (BAC) Calculator
Result
Estimated BAC
0.04%
- Status
- Below 0.05
- Hours until BAC = 0
- 2.7 h
How it's calculated
BAC% = (grams alcohol / (weight_kg × 1000 × r)) × 100 − 0.015 × hours
Common questions
Is this accurate enough to decide whether to drive?
No. This is a rough estimate. Do not drive after drinking regardless of what the number says.
What is a 'standard drink'?
About 14 g of pure alcohol — roughly a 355 ml beer at 5%, 150 ml of wine at 12%, or a 44 ml shot of spirits at 40%.
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