When it comes to alcohol and safety, blood alcohol content (BAC) is an important metric that helps determine a person’s level of impairment. When you drink, your BAC is influenced not just by how much alcohol you’ve had in the past several hours, but by other factors like your sex, weight, and how your unique body processes alcohol.
But what exactly is BAC, and what do different BAC levels feel like? Below, find a simple blood alcohol content chart, symptoms of each blood alcohol level, and how to accurately test your BAC.
What Is Blood Alcohol Content (BAC)?
Blood alcohol content (BAC) is a number that reflects the alcohol concentration in a person’s body, calculated by the amount of alcohol (in grams) per 100 mL of blood. As an example, a BAC test showing 0.06 would mean that 0.06% of your blood’s volume is alcohol.
When you think of BAC, breathalyzers, drunk driving, or legal trouble might be the first things that come to mind. However, it can also be used in other situations where safety or health are important. For instance, employers might test for BAC in certain workplace settings, and nurses or doctors will check BAC when treating a person for alcohol poisoning.
What Factors Affect BAC?
BAC isn’t one-size-fits-all, and you might end up with a different BAC than someone else even if you’re drinking the same amount. With that in mind, the main factors that affect BAC include:
- How many drinks you’ve had
- How long it’s been since you drank
- The speed at which you’re drinking
- Your weight
- Your sex
- Whether or not you’ve eaten prior to drinking alcohol
- Any medications that impact your body’s ability to process alcohol
Schedule a private call with a Ria Health team member and we can help you get started.
Blood Alcohol Levels Explained
BAC can range anywhere from 0.01% (slightly “feeling it”) to 0.30%+, which is dangerously high. After a couple of drinks at a party or out with friends, many people find themselves in moderate or semi-high BAC ranges of 0.04%–0.10%.
Although these percentages might seem small, tiny variations in your BAC can greatly affect your body’s systems, cognition, and how drunk you feel — whether that’s tipsy or blackout drunk. At moderate-to-high BAC levels, it’s also common to experience exaggerated emotions like excitement, sadness, happiness, or even rage.
What Is a High BAC?
The definition of a “high” BAC can vary in different contexts. In legal situations, being too drunk to drive (over 0.08%) is a high BAC, but in medical settings, a high blood alcohol level might mean blacking out or having symptoms of alcohol poisoning.
Does Tolerance Affect BAC?
In short, no. It’s a common myth that having a high tolerance can affect your BAC. In fact, many heavy drinkers believe that because they have a high tolerance, they will have a lower BAC than someone of a similar size drinking the same amount of alcohol — simply because their body is more “used to it.”
The truth is that tolerance does not affect BAC, but instead makes your body and mind more resistant to the effects of alcohol, even at high BAC levels. If you’ve developed a high tolerance and want to better gauge whether your drinking is normal, you can take a brief 11-question quiz or sign up for a Ria Health consultation to learn more.
Blood Alcohol Content Chart
This blood alcohol chart can help you understand roughly what each blood alcohol level feels like (many of these effects can “stack” onto each other as BAC rises).:
| Percentage | Impairment Level | Effects |
|---|---|---|
| 0.02% –0.04% | Lightheaded or “loose” | Light euphoria and relaxation |
| 0.04% –0.07% | Buzzed or tipsy | Greater euphoria, a decrease in shyness and inhibitions, louder speaking, more animated behavior, and exaggerated emotions |
| 0.08% –0.10% | Legally impaired | Impaired motor skills, slightly slurred speech, blurry vision, slower reaction time, and poorer judgment |
| 0.11% –0.15% | Drunk | Profound impairments in motor skills, speech, hearing, and vision. More marked depressive effects of alcohol, impaired perception, and disorientation |
| 0.16% –0.20% | Very drunk | Stumbling, lack of balance, difficulty communicating, nausea or vomiting; potentially inappropriate behavior |
| 0.21%–0.24% | Delirious, severely impaired | Possible blackout, loss of memory, lack of self-control, and unfazed or oblivious to pain |
| 0.24%–0.30% | Dangerously intoxicated | All areas of cognition are profoundly affected. Many pass out and/or vomit. High risk of harm due to depressive effects and near-complete lack of physical and emotional control |
| 0.31%–0.35% | Risk of coma or acute alcohol poisoning | Coma, loss of consciousness, and acute alcohol poisoning likely; seek medical attention |
| 0.35%+ | Coma or fatal | Highly life-threatening, coma or death may occur; immediate medical attention is required |
How Do You Test Your BAC?
Knowing how to accurately test your BAC can help you abide by laws and stay safe, and it’s especially important if you plan on driving when the alcohol wears off. However, calculating exactly how drunk you are can be challenging, even if you’re counting your drinks or using tools like blood alcohol content charts.
Because your BAC is impacted by many factors unique to you, the only 100% concrete way to know your BAC is through tests like:
- Breathalyzers, which determine your BAC based on the amount of alcohol expelled from your lungs while breathing.
- Blood tests, which directly measure the amount of alcohol in your bloodstream.
Because most people won’t have easy access to tools like these, a general rule of thumb is to not drive if you feel buzzed or tipsy. It can also be helpful to remember that, on average, your body can process one drink per hour, but this can vary based on other factors that affect your alcohol metabolism.
What About BAC Calculators?
For a more specific BAC estimate, you can use a BAC calculator that factors in your weight, sex, the number of standard-sized drinks you’ve had, and the time that’s passed since your last drink.
Disclaimer: These tools have limitations and are not a foolproof way to know your BAC, so they should not be used to decide whether or not to drive.
Feeling Concerned About Your BAC?
If you drink heavily or have been worrying about your BAC often, it might be a sign that you’re struggling with alcohol abuse or dependence. While you might feel like it’s under control — or that you can manage it on your own — know that you don’t have to do it alone.
Programs like Ria Health can connect you with comprehensive support including one-on-one coaching, access to mental health professionals, and anti-craving prescriptions, all from the comfort of your home. Because you can access all of these resources from the Ria app, you won’t have to sign up for inpatient treatment, miss work, or rearrange your life to get support.
Get in touch with the Ria Health team to start better understanding and managing your drinking today, or learn more about how the program works.
