wikiHow Blood Alcohol Content Calculator The Widmark formula is one method used to estimate blood alcohol content (BAC) based on several factors, including the amount of alcohol consumed, body weight, and time elapsed since consumption. The formula is as follows: BAC = (Alcohol consumed in grams / (Body weight in grams × r)) × 100 Where: Alcohol consumed in grams refers to the amount of alcohol consumed in grams. Body weight in grams refers to the individual's body weight in grams. r is the Widmark factor, which is typically assumed to be 0.68 for men and 0.55 for women. The Widmark factor takes into account differences in body water content and alcohol metabolism between genders. Here are the steps to calculate BAC using the Widmark formula: 1. Convert body weight to grams if it's in kilograms. Multiply the body weight in kilograms by 1000 to convert it to grams. 2. Determine the amount of alcohol consumed in grams. This can be calculated by multiplying the volume of alcohol consumed (in milliliters) by the alcohol percentage (expressed as a decimal) and the density of ethanol (which is approximately 0.789 g/mL). 3. Calculate the BAC using the Widmark formula: divide the alcohol consumed in grams by the product of body weight in grams and the Widmark factor (0.68 for men or 0.55 for women). Multiply the result by 100 to obtain the BAC as a percentage. Please note that the Widmark formula provides an estimate of BAC and individual variations in alcohol metabolism and other factors may influence the actual BAC. It's important to drink responsibly and never drive or engage in any activities that require alertness if you have consumed alcohol. Example: 1. Let's assume a man weighing 80 kilograms (80,000 grams) consumed 4 standard drinks. Each standard drink contains 14 grams of alcohol. 2. Calculate the amount of alcohol consumed in grams: Alcohol consumed = (Number of standard drinks) × (Grams of alcohol per standard drink) Alcohol consumed = 4 standard drinks × 14 grams of alcohol per standard drink Alcohol consumed = 56 grams 3. Calculate the BAC using the Widmark formula: BAC = (Alcohol consumed in grams / (Body weight in grams × r)) × 100 BAC = (56 grams / (80,000 grams × 0.68)) × 100 BAC ≈ 0.1035 × 100 BAC ≈ 10.35% In this example, based on the Widmark formula, the estimated BAC is approximately 10.35%. Please note that this is a hypothetical calculation and does not account for other individual factors that may affect alcohol metabolism and BAC. It's crucial to prioritize safety and adhere to legal limits regarding alcohol consumption and driving. Page