Body Mass Index (BMI) is a measure of body fat based on height and weight. The most common method of calculating BMI is the Quetelet formula (weight in kilograms / the square of height in meters). BMI is used to screen for weight-related health problems such as obesity, underweight, and eating disorders.
BMI was originally developed in the 19th century by Belgian statistician Adolphe Quetelet. It is now used by healthcare professionals worldwide as a simple and inexpensive way to assess body weight status. In addition to its clinical use, BMI is also used to track population trends in weight-related health problems.