Monu Tools

Blood Alcohol Calculator

Estimate your blood alcohol concentration in per mille with the Widmark formula, based on the drink, your weight and the time elapsed.

How to use the Blood Alcohol

  1. 01

    Pick a preset drink or enter the volume and alcohol percentage.

  2. 02

    Enter your body weight and select your sex.

  3. 03

    Set the hours since you started drinking to see the current estimate.

Frequently asked questions

How is blood alcohol calculated?

It uses the Widmark formula: grams of pure alcohol divided by body weight times a distribution factor (0.7 for men, 0.6 for women). About 0.15 per mille per hour is subtracted for elimination.

How accurate is it?

It is a rough estimate. Food, drinking speed, metabolism, medication and individual differences all change the real value, so treat the result as a guide only.

Can I rely on it to drive?

No. Never use a calculator to decide whether you are fit to drive. The only safe amount of alcohol before driving is none.

About this tool

A blood alcohol calculator that estimates your per mille level from a drink, your weight and sex using the well-known Widmark formula, and shows roughly when you would be sober again.

It is meant for education and curiosity, not as a legal or medical reference, and never as a basis for deciding to drive.

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