Calculate Blood Alcohol Content (BAC) based on drinks consumed, time elapsed, gender, and body weight. Get safety information and understand alcohol effects on your body.
This calculator provides estimates only and should never be used to determine if it's safe to drive or operate machinery.
Always designate a sober driver or use alternative transportation after drinking alcohol.
Blood Alcohol Content (BAC) is a measure of the amount of alcohol in a person's bloodstream. It is typically expressed as a percentage of alcohol per volume of blood. For example, a BAC of 0.08% means there are 0.08 grams of alcohol per 100 milliliters of blood.
BAC is influenced by several factors including the amount of alcohol consumed, body weight, gender, time elapsed since drinking, and food consumption. Understanding BAC levels is crucial for making informed decisions about alcohol consumption and ensuring personal and public safety.
| Country/Region | Legal Limit (Driving) | Zero Tolerance | Commercial Drivers |
|---|---|---|---|
| United States | 0.08% | Under 21: 0.01-0.02% | 0.04% |
| Canada | 0.08% | New drivers: 0.00% | 0.04% |
| United Kingdom | 0.08% | New drivers: 0.00% | 0.08% |
| Australia | 0.05% | Learner/P-plate: 0.00% | 0.02% |
| Germany | 0.05% | Under 21: 0.00% | 0.05% |
| Japan | 0.03% | Professional: 0.00% | 0.03% |
| BAC Range | Effects on Behavior | Physical Impairment | Risk Level |
|---|---|---|---|
| 0.01-0.03% | Slight euphoria, relaxation | No visible impairment | Minimal |
| 0.04-0.06% | Feeling of well-being, talkativeness | Slight impairment of reasoning | Low |
| 0.07-0.09% | Disinhibition, overconfidence | Motor control impairment | Moderate |
| 0.10-0.12% | Boisterousness, possible nausea | Significant motor impairment | High |
| 0.13-0.15% | Emotional swings, anxiety | Gross motor impairment | Very High |
| 0.16-0.30% | Stupor, confusion | Risk of coma, death | Critical |
| 0.30%+ | Unconsciousness | Life-threatening | Fatal |
| Beverage Type | Standard Serving | Alcohol Content | Pure Alcohol |
|---|---|---|---|
| Beer (Regular) | 12 oz (355 ml) | 5% | 14g (0.6 oz) |
| Wine | 5 oz (150 ml) | 12% | 14g (0.6 oz) |
| Spirits | 1.5 oz (44 ml) | 40% | 14g (0.6 oz) |
| Fortified Wine | 3.5 oz (100 ml) | 18% | 14g (0.6 oz) |
| Light Beer | 12 oz (355 ml) | 4.2% | 12g (0.5 oz) |
Absorption: Alcohol is rapidly absorbed into the bloodstream through the stomach and small intestine. Peak BAC typically occurs 30-90 minutes after consumption on an empty stomach.
Distribution: Once in the bloodstream, alcohol is distributed throughout the body's water content. Because women generally have less body water than men, they achieve higher BAC levels.
Metabolism: The liver is responsible for metabolizing about 90% of consumed alcohol. The average person metabolizes alcohol at a rate of about 0.015% BAC per hour.
Elimination: Small amounts of alcohol are eliminated through breathing, sweating, and urination, but the liver does most of the work.
Acute Risks: High BAC levels can lead to alcohol poisoning, which can be fatal. Symptoms include confusion, vomiting, seizures, slow breathing, and unconsciousness.
Chronic Risks: Regular heavy drinking can lead to liver disease, cardiovascular problems, increased cancer risk, and addiction.
Interaction Risks: Alcohol can dangerously interact with many medications, including over-the-counter drugs.
Alcohol Poisoning Signs: Mental confusion, vomiting, seizures, slow or irregular breathing, hypothermia, or unconsciousness require immediate medical attention.
Addiction Concerns: If you find it difficult to control your drinking or if alcohol is interfering with your life, consider seeking professional help.
Emergency Situations: Call emergency services immediately if someone has consumed a dangerous amount of alcohol or is showing signs of alcohol poisoning.