BMI Calculator


About BMI

Our BMI calculator uses your weight and height to calculate your body mass index (BMI). BMI is an estimate of body fat derived from an individual's height and weight. This calculator is for adult men and women.

BMI is an abbreviation of Body Mass Index.

A BMI value is obtained by dividing an individual's weight (kg) by height (m) squared.

In the US, it is common to adjust the formula to work with standard weight and height measures (the original formula uses metric values). To calculate BMI using pounds and inches, an individual's weight in pounds (lb) is divided by their height in inches (in) squared and the result is then multiplied by 703.

The resulting value is then classified as underweight, normal, overweight, or obese by reference to ranges issued by an appropriate health organization.

A BMI calculator is a useful tool to determine an individual's BMI value since the calculator automatically computes the BMI from a user's weight and height.

How to Use the Body Mass Index Calculator

  1. Choose Standard or Metric
  2. Enter your weight and height
    Standard: Enter your weight in pounds (lb) and height in feet (ft) and inches (in).
    Metric: Enter your weight in kilograms (kg) and height in centimeters (cm).
  3. Click Calculate

History of BMI

The index was originally known as the Quetelet Index and was first devised by the Belgian polymath and founding social scientist, Adolphe Quetelet in 1832.[1] One hundred and forty years later, the American physiologist Ancel Keys coined the term Body Mass Index by which we know the Quetelet Index today.[1]

Quetelet did not intend that the Quetelet Index be used to assess the obesity or health status of individuals but was interested in the statistics of various human attributes in populations.[1] Quetelet found that the height-weight of a population as measured using the Quetelet Index fits the Gaussian curve whereas a simple height to weight ratio does not.

Application to Individuals

Today, the BMI is widely used as an indirect measure of the amount of fatness, since, despite its shortcomings, it is a simple and relatively reliable tool. A recent article in the International Journal of Epidemiology noted, the "standard BMI has survived as a robust, useful and surprisingly accurate measure of fatness in 'healthy' adults"[1]

While the BMI can contribute to an assessment of an individual's weight and health status, it is to be noted that it is not a direct measure of either weight or health.

BMI Formula

BMI = Mass-kg Divided by heightm2
BMI = Mass-lb Divided by heightin2 x 703

BMI Limitations

  • BMI does not account for muscle mass
  • BMI does not function for correctly for all ages
  • BMI can vary due to race/ethnicity
  • BMI is not directly related to health


Disclaimer: All calculators, tools, and results featured on are to be finalized and not be considered a quotation or binding contract.
Proofs and formulas are provided as references.