Printed on 3/17/2026
For informational purposes only. This is not medical advice.
This BAC calculator provides an educational estimate of blood alcohol concentration (BAC) using a Widmark-style formula based on standard drinks consumed, body weight, biological sex, and elapsed time. It is intended for risk awareness and should never be used to determine whether driving or operating machinery is safe. For formal alcohol use disorder screening, use [AUDIT Score](/tools/audit) (10-item) or [CAGE Questionnaire](/tools/cage) (4-item). Chronic heavy alcohol use causes liver disease — assess hepatic severity with [MELD Score](/tools/meld-score) and [Child-Pugh Score](/tools/child-pugh). Body weight affects BAC — check [BMI Calculator](/tools/bmi-calculator) for weight context.
Formula: Widmark-style estimate: BAC from alcohol grams, body-weight distribution factor, minus time-based elimination
Your estimated BAC provides a rough intoxication range and impairment context. As BAC rises, reaction time, coordination, judgment, and risk-taking are increasingly affected.
Values at or above common legal thresholds indicate high safety risk and legal exposure, but impairment can occur well below 0.08%. Treat this output as conservative risk awareness, not clearance for any activity.
Use this tool for educational awareness about alcohol exposure and impairment risk patterns. It can support harm-reduction counseling and personal planning discussions.
It is not a forensic, legal, or medical measurement device and should not be used for legal defense, workplace fitness decisions, or emergency triage.
BAC modeling assumptions are population averages. Real-world variation is substantial due to beverage strength, pour size, sex/hormonal factors, gastric emptying, liver function, medications, genetics, and concurrent substances.
The estimate does not account for ongoing drinking, vomiting, recent food differences in absorption, or breath/blood measurement device variability. If intoxication or poisoning is a concern, seek in-person medical evaluation.
For related assessments, see AUDIT, CAGE and Calorie Calculator.
Disclaimer: This tool is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider with questions about your health.
Screen for hazardous and harmful alcohol use with the 10-question AUDIT. Scores range from 0 to 40 across four risk zones. For quick screening use [CAGE](/tools/cage).
Mental HealthQuick four-question alcohol screening using the CAGE questionnaire. A score of 2 or more suggests possible alcohol problems. For comprehensive screening, use [AUDIT](/tools/audit).
NutritionCalculate your daily calorie needs based on the Mifflin-St Jeor equation. Get personalized BMR, TDEE, and target calories for weight loss, maintenance, or gain.
NutritionCalculate your recommended daily water intake based on body weight and activity level. Stay properly hydrated with personalized recommendations.