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Alcohol Metabolism & BAC Calculator

Calculate estimated blood alcohol limits using clinical formulas, tracking metabolic decay until sobriety.

Body Profile & Drinks Consumed
Provide your details and standard drink counts to estimate blood alcohol concentrations.

Drinks Added

Beer (12oz, 5% ABV): 2
Wine (5oz, 12% ABV): 0
Spirits (1.5oz shot, 40% ABV): 0
Time since first drink: 2 hours
Metabolism Analysis
Real-time calculation using biological formulas.

Mild Impairment

0.023% BAC

Coordination & reaction speed are reduced. Driving is not recommended.

Time to Sobriety

1h 30m

At a metabolism rate of ~0.015% BAC per hour.

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BAC Sobriety Calculator

Calculated approximate alcohol decay and sobriety times.

0.023% BAC

Mild Impairment

Total Drinks:2

Time to Sober:1h 30m

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The Science of Alcohol Metabolism

Once consumed, alcohol is absorbed into the bloodstream through the stomach and small intestine. Because alcohol is water-soluble, it distributes itself throughout the body's water content.

The liver is responsible for metabolizing over 90% of the alcohol in your body. It does so at a fixed rate, regardless of factors like coffee intake or exercise.

The Widmark Formula

The Widmark formula is the clinical standard for calculating Blood Alcohol Concentration (BAC):

BAC = [ (A × 5.14) / (W × r) ] - (0.015 × H)

  • A (Alcohol in ounces): Pure ethanol consumed. One standard US drink contains approx. 0.6 oz of pure alcohol.
  • W (Weight in lbs): Body weight.
  • r (Gender distribution constant): Men average more body water (0.73), while women average less body water (0.61).
  • $\beta$ (Metabolic decay rate): The rate at which the body clears alcohol. The clinical average is 0.015% per hour.
  • H (Hours): Total hours elapsed since drinking began.

Frequently Asked Questions

References & Scientific Sources

  • Widmark, E. M. P. (1932). Die theoretischen Grundlagen und die praktische Verwendbarkeit der gerichtlich-medizinischen Alkoholbestimmung. Berlin: Urban & Schwarzenberg.
  • National Institute on Alcohol Abuse and Alcoholism (NIAAA). Understanding Alcohol Use Disorder and Blood Alcohol Limits. National Institutes of Health.
  • Federal Aviation Administration (FAA). Alcohol and Flying: A Pilot's Guide. Office of Aerospace Medicine.