How to Use Blood Alcohol (BAC) Calculator
Estimate your blood alcohol content from drinks, weight and time.
Open the Blood Alcohol (BAC) Calculator tool →What is Blood Alcohol (BAC) Calculator?
Estimate your blood alcohol content from drinks, weight and time. It's completely free, needs no sign-up, and runs entirely in your browser — so it's fast and private.
How to use Blood Alcohol (BAC) Calculator
- Open the Blood Alcohol (BAC) Calculator tool.
- Enter your details or values.
- The result is calculated instantly.
- Copy or use the result. Everything runs in your browser — nothing is uploaded.
Frequently asked questions
How is BAC estimated?
Using the Widmark formula from your weight, sex, standard drinks and time since your first drink.
Can I use it to decide whether to drive?
No — it's only a rough estimate and many factors affect real BAC. If you drink, don't drive.
Ready to try it?
Open Blood Alcohol (BAC) Calculator →