Blood Alcohol (BAC) Calculator
Estimate your blood alcohol content from the number of drinks, your weight and time. This is a rough educational estimate only.
⚠️ Estimate only. Many factors affect real BAC. Never use this to decide if it's safe to drive — if you've been drinking, don't drive.
How to use the Blood Alcohol (BAC) Calculator
- Enter sex, weight, drinks and time.
- Click Estimate BAC.
- Read the estimate (educational only).
100% free, no sign-up, and it all runs in your browser — your data never leaves your device.
FAQ
What is a standard drink?
About 14g of pure alcohol: a 12oz/355ml regular beer, a 5oz/150ml glass of wine, or a 1.5oz/44ml shot of spirits.
Can I trust this to drive?
No. BAC depends on many personal factors this can't capture. Treat the number as educational only and never drive after drinking.