Blood Alcohol Concentration (BAC) Calculator
Modify the values and click the calculate button to use
Personal Information
Time Since First Drink
Amount of Alcohol Consumed
| Type | Amount | Size | ABV |
|---|---|---|---|
| Beer | |||
| Wine | |||
| Liquor | |||
| Other |
% ABV | ||
Your Estimated Blood Alcohol Concentration (BAC)
Note: This calculator provides only an estimate of your BAC. Many factors can affect BAC, including food consumption, metabolism, medication, and health conditions. Always drink responsibly and never drive after drinking.
What is Blood Alcohol Concentration (BAC)?
Blood Alcohol Concentration (BAC) measures alcohol intoxication. It shows the grams of alcohol per 100 milliliters of blood. A BAC of 0.08% means 0.08 grams of alcohol per 100 ml of blood.
Legal BAC Limits for Driving
Knowing the law is crucial for safe driving.
- Drivers 21 and over: The legal limit is 0.08%. Driving at or above this is a DUI/DWI offense.
- Underage drivers: All states have "zero-tolerance" laws. Limits range from 0.00% to 0.02%. Any detectable alcohol can lead to penalties.
For more details, visit the National Highway Traffic Safety Administration (NHTSA).
How Alcohol Affects Your Health
Alcohol impacts your health in both short-term and long-term ways.
Potential Health Risks
Drinking carries significant risks.
- Impairs judgment and coordination. It can cause dehydration and alcohol poisoning.
- Heavy use raises the risk of liver disease, heart damage, various cancers, and alcohol use disorder.
The National Institute on Alcohol Abuse and Alcoholism (NIAAA) provides extensive resources on these risks.
Are There Any Health Benefits?
Some studies suggest light drinking may offer benefits. These include a lower risk of heart disease or ischemic stroke. However, health experts warn against starting to drink for these reasons. The benefits are small and uncertain. They are often outweighed by the risks. Other lifestyle factors may explain these results.
What is Moderate vs. Heavy Drinking?
Understanding drinking levels is key to safety.
- Moderate Drinking: Up to 1 drink daily for women. Up to 2 drinks daily for men.
- Heavy Drinking: For women, 4+ drinks in a day or 8+ per week. For men, 5+ drinks in a day or 15+ per week.
Heavy drinking has no health benefits. It greatly increases health risks. Always talk to a doctor about what is safe for you. Explore our guide on understanding standard drink sizes for more clarity.
BAC Levels and Their Effects
Your impairment increases as your BAC rises.
| BAC Level | Common Effects and Impairments |
|---|---|
| 0.02% | Relaxation, slight warmth, minor loss of judgment. |
| 0.05% | Exaggerated behavior, loss of small-muscle control, impaired judgment. |
| 0.08% (Legal Limit) | Poor muscle coordination, slower reaction times, reduced self-control. |
| 0.10% | Clear deterioration of coordination, slurred speech. |
| 0.15% | Major loss of balance, vomiting, unable to drive safely. |
| 0.30% and above | Risk of coma, unconsciousness, and potential death from alcohol poisoning. |
Note: Effects can vary based on tolerance, gender, weight, and food intake.
Key Takeaways
Understanding your BAC is vital for safety and legality. Always know your limits. Never drive after drinking. Consider your personal health before consuming alcohol. For help with alcohol use disorder, contact the Substance Abuse and Mental Health Services Administration (SAMHSA) helpline at 1-800-662-HELP (4357).
BAC Levels and Their Effects: A Detailed Chart
The effects of alcohol intensify dramatically as your BAC rises. The following table outlines the common impairments and behaviors associated with increasing BAC levels.
| BAC Level (%) | Common Behaviors & Symptoms | Key Impairments |
|---|---|---|
| 0.010 – 0.029 | Appearing normal; no obvious signs. | Subtle effects detectable only by specialized tests. |
| 0.030 – 0.059 | Mild euphoria, relaxation, increased talkativeness, lowered inhibitions. | Beginnings of impaired concentration and judgment. |
| 0.06 – 0.099 | Blunted feelings, reduced pain sensitivity, heightened euphoria, disinhibition. | Clearly impaired reasoning, depth perception, peripheral vision, and glare recovery. |
| 0.10 – 0.199 | Over-expression, boisterousness, emotional instability, nausea, vomiting. | Significantly slowed reflexes, poor reaction time, loss of motor control, staggering gait, slurred speech. |
| 0.20 – 0.299 | Nausea, vomiting, confusion, intense emotional swings, possible stupor. | Severe motor impairment, mental confusion, memory blackouts, loss of consciousness. |
| 0.30 – 0.399 | Stupor, central nervous system depression, lapses in consciousness. | Major functions impaired: bladder control, breathing, heart rate, equilibrium. Risk of death. |
| 0.40 – 0.50 | Coma, severe CNS depression. | Breathing and heart rate are dangerously suppressed. High risk of death from alcohol poisoning. |
| >0.50 | This level is considered a severe medical emergency and is often fatal. |
Key Takeaway
Understanding your BAC is critical for making safe decisions, especially regarding driving. While moderate alcohol consumption may fit into some lifestyles, it is not without risk and is not recommended as a health strategy. The safest approach is to be fully aware of the profound impairments caused by rising BAC levels and to prioritize your health and safety by drinking responsibly, if you choose to drink at all. Always seek personalized advice from a medical professional.