Blood Alcohol Concentration Calculator
Estimate Blood Alcohol Content (BAC) and metabolic clearance time based on the clinical Widmark equation.
About the Widmark BAC Formula
Blood Alcohol Concentration (BAC) quantifies the metric grams of alcohol per 100 milliliters of circulating blood, establishing clinical and legal impairment levels.
Standard Drink Equivalence
One standard drink corresponds to 14 grams of pure ethanol: roughly 350 ml of 5% beer, 150 ml of 12% wine, or 44 ml of 40% spirits.
Frequently Asked Questions
What is the statutory legal driving limit in most jurisdictions?
Many jurisdictions enforce a per se operating limit of 0.08% BAC, while others mandate lower limits of 0.05% or zero tolerance for novice drivers.
Can coffee or cold showers accelerate sobering up?
No. Hepatic alcohol dehydrogenase clears alcohol at a fixed metabolic rate of approximately 0.015% BAC per hour, unaffected by stimulants.
Why does BAC vary by biological sex?
Females generally have lower gastric alcohol dehydrogenase enzyme levels and a lower total body water percentage, concentrating alcohol faster.
Is this calculation legally admissible?
No. Theoretical estimates cannot replace evidentiary breath, blood, or chemical laboratory analysis.
Calculate in three steps
- 1Enter your valuesUse the fields above and check the units shown beside each input.
- 2Run the calculationSelect Calculate to refresh the result with your latest values.
- 3Review or shareCompare the result, reset the form, print it, or share this page.