# The BAC calculator formula

A description of how we calculate the residual alcohol in the blood.

This is a brief description of the algorithm, which is used in the program to calculate the residual alcohol in the blood. Each consumed beverage is characterized by two parameters - its volume and alcohol content. Based on these parameters we can calculate the amount of alcohol contained in the beverages using the following formula:

weight = (volume * alcohol * 0.8) / 100 [g]

The resulting weight in grams is the total amount of pure ethanol, which is contained in the drink. The volume of drink in this formula is entered in milliliters, and the density value of 0.8 represents ethanol. Actual value per mille can be calculated using the formula:

Per mille = weight / (weight * r) [g / kg]

Where weight is the total amount of ethanol in grams and the weight is the weight in kilograms of the consumer. The constant r represents the percentage of body water. For men take the values of 0.7 and 0.6 for women. The human body has the ability to eliminate alcohol from your body. The decrease of blood alcohol per hour is referred to as factor beta. Using the following formula you can calculate the mass of alcohol as it decreases in the body in one hour:

weight = weight * beta [g]

Weight is the total amount of ethanol in grams as it decreases in the body in one hour. Weight in kilograms is the consumer and a constant beta is according to professional sources, for men 0.1 and 0.085 for women and shows how many grams of alcohol per hour it decreases to 1 kilogram of live weight.

For data entered using the imperial system the input and output data is recalculated.

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