The Harris–Benedict equation (also called the Harris-Benedict principle) is a method used to estimate an individual's basal metabolic rate (BMR).

The estimated BMR value may be multiplied by a number that corresponds to the individual's activity level; the resulting number is the approximate daily kilocalorie intake to maintain current body weight.

The Harris–Benedict equation may be used to assist weight loss — by reducing the kilocalorie intake number below the estimated maintenance intake of the equation.