BAC Calculator

For educational purposes only. Do not use to make decisions about driving or consuming alcohol. If you drink, don't drive.

Gender

Weight (kg)

Hours Since First Drink

Drinks

Beer (355ml)

Wine (148ml)

Liquor (44ml)

Shot (44ml)

Cocktail

BAC Calculator

The BAC Calculator gives an educational estimate of blood alcohol content from the drinks consumed, body weight, sex, and time elapsed - to illustrate how alcohol is processed.

How BAC is estimated

It uses the Widmark formula, which estimates BAC from the grams of alcohol consumed, body weight, a sex-based distribution factor, and the alcohol metabolised over time (the body clears roughly 0.015% BAC per hour). This shows why the same drinks affect people differently and why time - not coffee or a cold shower - is the only thing that truly sobers you up.

Important safety note: This tool is for education only. It cannot account for your individual metabolism, medications, food, or health, and must never be used to decide whether it is safe or legal to drive. If you have consumed any alcohol, do not drive.

Frequently Asked Questions

How does the body clear alcohol?

The liver metabolises alcohol at a fairly fixed rate, lowering BAC by roughly 0.015% per hour. Nothing reliably speeds this up - only time reduces BAC.

Can I use this to decide if I can drive?

No. Absolutely not. It is an educational estimate only and cannot reflect your real impairment. If you have been drinking, do not drive.

Why does BAC differ between people?

Body weight, sex, body composition, food, medication, and individual metabolism all affect BAC, so identical drinks produce different results.

What formula does it use?

It uses the Widmark formula, a well-known method for estimating blood alcohol content, adjusted for time since drinking.