Harris Benedict BMR
Calculator

The Harris-Benedict equation, originally published in 1919 and revised in 1984, calculates basal metabolic rate from weight, height, age, and sex using its own specific coefficients. It's one of the older and more historically established formulas, though newer equations like Mifflin-St Jeor are now often considered more accurate for contemporary populations.

Studies have found the original Harris-Benedict formula tends to overestimate BMR, particularly in people who are overweight, because it was developed using data from a population with different average body compositions than today. This is one reason later formulas were developed to improve accuracy.

The revised 1984 version adjusted the original coefficients based on updated data and is generally the more commonly used and recommended version today. This calculator typically uses the revised formula unless otherwise specified.

Multiply the BMR result by an activity multiplier that reflects your typical daily movement, ranging from around 1.2 for sedentary lifestyles up to 1.9 for very intensely active individuals, to estimate your total daily energy expenditure. This total, not the raw BMR, is the number to compare against your calorie intake for weight goals.

Some people use Harris-Benedict for consistency with historical tracking, comparison with older clinical literature, or because a specific program or clinician requests it, but for a fresh accuracy-focused estimate, Mifflin-St Jeor is generally preferred by dietitians today. Either formula gives a reasonable starting estimate, not an exact figure.