Question
Can I use this to decide whether to drive?
No. This is only an estimate. Real BAC and impairment can differ materially, and legal limits vary by jurisdiction. The safe choice is to avoid driving after drinking.
Fitness
Use OmniCalc's BAC calculator to estimate blood alcohol concentration from drinks consumed, drink size, alcohol strength, body weight, and time elapsed.
BAC calculator
Use body weight, drink count, drink strength, and time elapsed to estimate BAC with a simple Widmark-style formula.
This estimate is educational only. It cannot account for food, metabolism differences, medications, health conditions, or local legal rules.
Why this result matters
A practical public-health estimate tool that uses a Widmark-style formula to estimate BAC from drinks, alcohol strength, weight, and time. Use the tool above to enter a few clear inputs and get a practical answer you can use right away.
This BAC calculator estimates blood alcohol concentration from body weight, drink count, drink size, alcohol percentage, and time since drinking started. It is useful for education and rough planning, but it is not a legal or medical reading and should never be used to decide whether it is safe to drive.
Formula and method
The calculator uses a Widmark-style estimate that combines body weight, sex-based alcohol distribution ratio, pure alcohol consumed, and a simple hourly elimination factor.
Example
If someone enters three 12-ounce drinks at 5% ABV, a body weight of 180 lb, and two hours since the first drink, the calculator estimates BAC and shows a simple interpretation band.
FAQ
Short answers to the questions people often ask before or after using the tool.
Question
No. This is only an estimate. Real BAC and impairment can differ materially, and legal limits vary by jurisdiction. The safe choice is to avoid driving after drinking.
Question
Food intake, metabolism, health conditions, medication use, drink pacing, and measurement assumptions can all change real BAC compared with a formula result.
Question
It is a comparison against a common legal threshold used in many places, but not all. Local laws and lower-risk choices still matter.
Related calculators
If the next question is close to this one, these are the best pages to open next.
Fitness
Use OmniCalc's calorie calculator to estimate daily calorie needs for maintenance, weight loss, or weight gain goals.
Fitness
Use OmniCalc's body surface area calculator to estimate BSA from height and weight with several common formulas.
Fitness
Use OmniCalc's GFR calculator to estimate kidney filtration from serum creatinine, age, and sex.
Fitness
Use OmniCalc's healthy weight calculator to estimate a BMI-based healthy weight range from your height.