Body Mass Index - BMI


The body mass index (BMI), or Quetelet index, is a heuristic proxy for human body fat based on an individual’s weight and height.

BMI provides a simple numeric measure of a person’s thickness or thinness, allowing health professionals to discuss overweight and underweight problems more objectively with their patients. However, BMI has become controversial because many people, including physicians, have come to rely on its apparent numerical authority for medical diagnosis, but that was never the BMI’s purpose; it is meant to be used as a simple means of classifying sedentary (physically inactive) individuals, or rather, populations, with an average body composition.
For these individuals, the current value settings are as follows: a BMI of 18.5 to 25 may indicate optimal weight, a BMI lower than 18.5 suggests the person is underweight, a number above 25 may indicate the person is overweight, a number above 30 suggests the person is obese.

Related formulas


BMIBody Mass Index (kg/m2)
mmass (kg)
hheight (m)