BAC Calculator
Calculate Your Blood Alcohol Content
Enter your information below to calculate your estimated blood alcohol content (BAC) using the scientifically validated Widmark formula.
How BAC Calculation Works
Widmark Formula
We use the scientifically validated Widmark formula to calculate BAC based on alcohol consumed, body weight, and gender.
Body Water Content
Men typically have 68% body water content, while women have 55%, affecting alcohol distribution in the body.
Metabolism Rate
The average person metabolizes alcohol at approximately 0.015% BAC per hour, regardless of consumption amount.
Time Factors
We account for drinking duration and time elapsed since last drink to provide current BAC estimates.
Understanding BAC Levels
- Normal behavior and judgment
- No noticeable effects
- Safe to drive and operate machinery
- Slight euphoria and relaxation
- Minor impairment of reasoning and memory
- Lowered caution and inhibitions
- Driving ability may be affected
- Definite impairment of motor coordination
- Loss of good judgment and self-control
- Slurred speech and poor coordination
- Illegal to drive in most jurisdictions
- Major loss of motor control
- Vomiting and loss of consciousness possible
- Potential for life-threatening alcohol poisoning
- Seek immediate medical attention
Factors That Affect Your BAC
Body Weight
Heavier individuals typically have lower BAC levels when consuming the same amount of alcohol due to greater body mass and water content.
Gender
Women generally have higher BAC levels than men due to lower body water content and differences in alcohol metabolism.
Food Consumption
Eating before or while drinking slows alcohol absorption, reducing peak BAC levels but not eliminating impairment.
Drinking Rate
Consuming alcohol quickly leads to higher peak BAC levels than drinking the same amount over a longer period.
Medications
Many medications can interact with alcohol, potentially increasing impairment or affecting metabolism rates.
Health Conditions
Liver function, overall health, and certain medical conditions can significantly affect how your body processes alcohol.
Frequently Asked Questions
How accurate is this BAC calculator?
Our calculator uses the medically validated Widmark formula, which provides estimates within a reasonable range for most people. However, individual factors like metabolism, health conditions, and medications can affect actual BAC levels. This tool is for educational purposes only.
What is the legal BAC limit for driving?
In most countries, the legal BAC limit is 0.08% (0.05% in some jurisdictions). However, impairment can occur at lower levels, and some areas have zero-tolerance policies for certain drivers. Always check your local laws.
How long does it take for BAC to return to zero?
The average person metabolizes alcohol at approximately 0.015% BAC per hour. This rate cannot be accelerated by coffee, cold showers, or other remedies. Only time allows your body to eliminate alcohol.
Why do men and women have different BAC calculations?
Men typically have higher body water content (68%) compared to women (55%). Since alcohol distributes in body water, women generally achieve higher BAC levels than men of the same weight consuming the same amount of alcohol.
Can I use this calculator to determine if I'm safe to drive?
This calculator provides estimates only and should never be used as the sole basis for driving decisions. Even at legal BAC levels, you may still be impaired. When in doubt, don't drive - use alternative transportation.
Important Safety Information
Educational Tool Only
This BAC calculator provides estimates based on scientific formulas but cannot account for all individual factors. Never rely solely on any calculator to determine fitness to drive or operate machinery.
Safety Guidelines
- Never drive if you've been drinking, regardless of calculated BAC
- Individual factors can significantly affect actual BAC levels
- Medications and health conditions influence alcohol metabolism
- When in doubt, wait longer or use alternative transportation
- Seek medical attention for signs of alcohol poisoning
- Consider professional help if drinking is affecting your life