Blood Alcohol Content (BAC) Calculator

Estimate blood alcohol content (BAC) using the Widmark formula, based on drinks consumed, body weight, sex, and time elapsed since drinking began. For educational purposes only — never use this to decide whether it's safe to drive.

Inputs

1 standard drink ≈ 14g of pure alcohol

Results
Estimated BAC
0.047

Try an example

Formula

BAC = (Alcohol(g) / (Weight(g) × r)) × 100 − 0.015 × hours, Widmark formula

Learn How This Works

Blood Alcohol Estimation and Daily Sugar Limits Explained

The Widmark BAC formula and the AHA added-sugar guideline explained with real worked examples.

Frequently Asked Questions

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