Blood Alcohol Calculator

Estimate BAC from drinks consumed, body weight, sex, and elapsed time.

Scratchpad (not saved)

kg

What This Calculator Does

Estimate BAC from drinks consumed, body weight, sex, and elapsed time.

It combines Standard Drinks, Weight, Sex, Hours Since First Drink to estimate Estimated BAC.

Formula & Method

Core equations: Widmark estimate: BAC=\frac{A\cdot5.14}{W\cdot r}-0.015H where A is alcohol oz, W weight lb, r distribution ratio, H hours elapsed.

Notation used in the formulas: R = Estimated BAC; x_{1} = Standard Drinks; x_{2} = Weight; x_{3} = Sex; x_{4} = Hours Since First Drink.

Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.

Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.

Inputs Used

  • Standard Drinks: Used directly in the calculation.
  • Weight: Used directly in the calculation.
  • Sex: Used directly in the calculation.
  • Hours Since First Drink: Used directly in the calculation.

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