What is Body Mass Index (BMI)?


Body mass index (BMI) is used to estimate the amount of body fat by using your height and weight measurements. It is a tool that can help assess risk factors for certain health conditions. The BMI is not always an accurate representation of body fat.  It is calculated by using weight in kilograms (kg) divided by the square of height in meters (m2).

In most people, BMI correlates to body fat — the higher the number, the more body fat you may have. The following table demonstrate the BMI for individuals with different height and weight.

CLICK to enlarge the chart

Diagnosing weight types (class) with BMI

  • Underweight: Less than 18.5.
  • Optimum range: 18.5 to 24.9.
  • Overweight: 25 to 29.9.
  • Class I obesity: 30 to 34.9.
  • Class II obesity: 35 to 39.9.
  • Class III obesity: More than 40.