Calculating Your Blood Alcohol Content
Last updated on May 15, 2026
Blood Alcohol Level Chart
One drink is considered:
- One beer
- One 3-ounce glass of wine
- One “shot,” or 1 ounce, of hard liquor
Drink and weight table
| Weight (lbs) | Number of Drinks | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | |
| 100 | 0.032 | 0.065 | 0.097 | 0.129 | 0.162 | 0.194 | 0.226 | 0.258 | 0.291 |
| 120 | 0.027 | 0.054 | 0.081 | 0.108 | 0.135 | 0.161 | 0.188 | 0.215 | 0.242 |
| 140 | 0.023 | 0.046 | 0.069 | 0.092 | 0.115 | 0.138 | 0.161 | 0.184 | 0.207 |
| 160 | 0.020 | 0.040 | 0.060 | 0.080 | 0.101 | 0.121 | 0.141 | 0.161 | 0.181 |
| 180 | 0.018 | 0.036 | 0.054 | 0.072 | 0.090 | 0.108 | 0.126 | 0.144 | 0.162 |
| 200 | 0.016 | 0.032 | 0.048 | 0.064 | 0.080 | 0.097 | 0.113 | 0.129 | 0.145 |
| 220 | 0.015 | 0.029 | 0.044 | 0.058 | 0.073 | 0.088 | 0.102 | 0.117 | 0.131 |
| 240 | 0.014 | 0.027 | 0.040 | 0.053 | 0.067 | 0.081 | 0.095 | 0.108 | 0.121 |
Below 0.06 (Lower Risk)
0.06 – 0.079 (Impaired)
0.08+ (Legally Intoxicated)
*This table is provided as a reference, and it should not be relied upon to determine whether you are capable of operating a motor vehicle. Always keep in mind that there are a number of variables that can influence whether you are legally qualified to drive. Questions regarding those variables should be addressed to experienced criminal defense lawyers.
If you have questions concerning the calculation of blood alcohol levels after a DWI arrest in Austin or elsewhere in Travis County or surrounding areas, please contact our Austin DWI attorneys at Hildreth & Rueda by calling 512-415-7648.
Understanding What Really Affects Your BAC
While charts and calculators can offer a general idea of how alcohol may affect your blood alcohol content (BAC), they cannot account for the many personal and biological factors that influence how quickly alcohol enters (and leaves) your system. Two people can drink the exact same amount and still end up with very different BAC levels. That’s why relying on a chart alone can create a false sense of certainty if you are facing an Austin DWI charge.
Several key factors can significantly change your BAC, including:
- Sex and body composition: Women typically reach a higher BAC than men after the same number of drinks because they tend to have less body water and more body fat. Alcohol stays more concentrated in water, not fat. Hormonal fluctuations, especially right before menstruation, can further increase BAC. Men also produce more of the enzyme that breaks down alcohol before it enters the bloodstream.
- Body size and build: Smaller-framed individuals and those with a higher proportion of body fat tend to exhibit higher BAC levels than larger, leaner individuals who drink the same amount of alcohol.
- How quickly you drink: Your body can metabolize only about one standard drink per hour. Drinking several drinks in a short time can cause your BAC to rise sharply before your body has a chance to process the alcohol.
- Food in your stomach: Drinking on an empty stomach allows alcohol to absorb quickly into the bloodstream. Eating before or while drinking slows this process, resulting in a lower and more gradual rise in BAC.
- The type and strength of the beverage: Drinks with a higher alcohol percentage raise BAC faster. Carbonated drinks can speed absorption, causing BAC to spike faster than expected.
- Container size and drink equivalents: A single glass of wine or mixed drink may contain more than one standard serving of alcohol. The number of standard drinks is what influences BAC.
- Time since your last drink: BAC can continue to rise even after you stop drinking because your body needs time to absorb what is already in your stomach.
- Other drugs or medications: These substances may not change your BAC, but they can intensify or mask the effects of alcohol. Stimulants may make you feel more sober than you are, while depressants can increase impairment.
Because of these variables, BAC charts and calculators should be viewed only as rough reference tools, not as a way to determine whether you can safely or legally drive. Even small miscalculations can place you above the legal limit without realizing it.
If you have questions concerning the calculation of blood alcohol levels or how BAC may be evaluated in your case, please contact our attorneys at Hildreth & Rueda by calling 512-415-7648 or reaching out online. Our experienced Austin DWI lawyers can help you understand your rights and the factors that may affect your situation.