BAC Calculator
Calculate your estimated Blood Alcohol Concentration (BAC) based on drinks consumed, body weight, gender, and time elapsed. Understand impairment levels and time to sobriety.
Formula:BAC = (Alcohol / (Weight × r)) - (0.015 × Hours)
Estimated BAC
Blood Alcohol
0.038%
Mild
Legal but impaired (under 0.08)
Hours to Sober~2.5 hrs
Drinks Processed1.0 of 2
This is an estimate only. Actual BAC varies. Never drink and drive.
Estimated BAC
Blood Alcohol
0.038%
Mild
Legal but impaired (under 0.08)
Hours to Sober~2.5 hrs
Drinks Processed1.0 of 2
This is an estimate only. Actual BAC varies. Never drink and drive.
Drinks Consumed
2 drinks
1 drinks15 drinks
1 hrs
0 hrs12 hrs
Your Information
lbs
Women typically have higher BAC due to body composition differences.
Effects at Your BAC Level
Mild(0.038% BAC)
- •Lowered inhibitions
- •Mild euphoria
- •Slight impairment of judgment
- •Decreased alertness
BAC Impairment Levels
0.00%Sober
0.02-0.05%Mild Impairment
0.05-0.08%Impaired
0.08%+Legally Drunk (US)
0.15%+Severe Impairment
0.30%+Life Threatening
What is a Standard Drink?
One standard drink contains approximately 0.6 oz (14g) of pure alcohol:
Beer
12 oz
5% ABV
Wine
5 oz
12% ABV
Liquor
1.5 oz
40% ABV
Malt Liquor
8 oz
7% ABV
Important Safety Information
- • This calculator provides estimates only. Actual BAC varies significantly between individuals.
- • Never drive after drinking. Use a designated driver, taxi, or rideshare.
- • Alcohol affects judgment before you feel drunk. Don't rely on how you feel.
- • If someone shows signs of alcohol poisoning (confusion, vomiting, seizures, slow breathing), call 911 immediately.
Explore Drinking Scenarios
Explore how changes affect your results
BAC Reference Comparison
Compared to the general population
Your BAC
3.8 % × 100
Percentile
40th
Below average - looking good!
Distribution
You
Sober
0.0
Social
2.0
Impaired
5.0
Legal Limit
8.0
Dangerous
15.0
Your Ranking
Top 40%
60% are higher
Safety Information
Based on your BAC results
0/4 completed
⚕️ MedicalOptional
Current Status
At 0.038% BAC, you have some alcohol in your system. Effects are minimal but present.
🌙 LifestyleRecommended
Time to Sober
Your body processes alcohol at about 0.015% per hour. You'll need approximately 2.5 hours to be fully sober.
🥗 NutritionOptional
Stay Hydrated
Drink water between alcoholic drinks. This doesn't reduce BAC but helps prevent dehydration and may reduce hangover symptoms.
Frequently Asked Questions
BAC measures the percentage of alcohol in your bloodstream. A BAC of 0.08% means 0.08 grams of alcohol per 100 milliliters of blood. This is the legal limit for driving in most US states.
This calculator uses the Widmark formula, which provides estimates based on average alcohol metabolism. Actual BAC varies based on food intake, medications, liver health, and individual metabolism. This is for educational purposes only.
The body metabolizes alcohol at about 0.015% BAC per hour (roughly one standard drink). A person with 0.08% BAC would take about 5-6 hours to become sober. Sleep, coffee, and cold showers do NOT speed up this process.
Key factors include: body weight (higher weight = lower BAC), gender (women typically have higher BAC per drink), food intake (food slows absorption), drinking speed, and individual metabolism.
Even below 0.08%, alcohol impairs judgment, reaction time, and coordination. Some states have lower limits (0.05%), and commercial drivers often have 0.04% limits. When in doubt, don't drive.
How this works
Uses the Widmark formula: BAC = (alcohol grams × 100) / (body weight in grams × distribution ratio) − hourly elimination rate × hours since first drink. Distribution ratio defaults to 0.68 (male) and 0.55 (female). Elimination averages 0.015% per hour.
What this tool can’t do
- Widmark is an average-body estimate; individual variation in enzyme levels, food intake, and hydration produces substantial differences.
- Never rely on a BAC calculator to decide whether it is safe to drive. If you have been drinking, do not drive.
When to consult a professional
Never use this tool as a legal or safety arbiter of whether you can drive, operate machinery, or perform any other BAC-regulated activity. The only safe BAC for driving is zero.
Sources
- [1]Centers for Disease Control and Prevention (CDC)Official sourcecdc.govAccessed Apr 21, 2026
- [2]National Institutes of Health (NIH)Official sourcenih.govAccessed Apr 21, 2026
Joseph OrdunaFounder & Software Engineer
Full-stack software engineer specializing in embedded systems, web architecture, and AI/ML. Founder of Practical Web Tools. Built the gesture-controlled drone IP acquired by KD Interactive (Aura Drone, sold on Amazon).
Estimated BAC
Blood Alcohol
0.038%
Mild
Legal but impaired (under 0.08)
Hours to Sober~2.5 hrs
Drinks Processed1.0 of 2
This is an estimate only. Actual BAC varies. Never drink and drive.