BAC Calculator

About BAC Calculator

BAC Calculator uses a Widmark-style estimate to turn body weight, elapsed time, and drink strength into an approximate blood alcohol concentration. It also shows the amount of pure alcohol consumed, the approximate number of standard drinks, and an estimated time until the level returns to 0%.

How To Use It

Enter body weight and elapsed time first, then add the drinks consumed so far.

• Choose male or female and enter body weight in pounds.
• Set the hours and minutes since the first drink, then add one or more drink rows with amount, size, and ABV.
• Click Calculate BAC to review the estimated concentration and recovery time.

Examples

• Two light beers

  Input:
  Gender: Male
  Body Weight: 176.4 lb
  Time Since First Drink: 1 hour 30 minutes
  Drink 1: 2 x 12 oz at 5% ABV
  
  Output:
  Estimated BAC: 0.025%
  Status: Low
  Time Until 0%: 1.7 hours

• Wine and spirits mix

  Input:
  Gender: Female
  Body Weight: 145 lb
  Time Since First Drink: 2 hours
  Drink 1: 1 x 5 oz at 12% ABV
  Drink 2: 1 x 1.5 oz at 40% ABV
  
  Output:
  Estimated BAC: 0.034%
  Status: Caution
  Time Until 0%: 2.3 hours