Calculate Your BMI

BMI Classification Health Risk
Under 18.5 Underweight Minimal
18.5 - 24.9 Normal Weight Minimal
25 - 29.9 Overweight Increased
30 - 34.9 Obese High
35 - 39.9 Severely Obese Very High
40 and Over Morbidly Obese Extremely High
*Note that these are approximate values, and are intended to be used only as a rough guide.

What is BMI

BMI is the most widely used measurement for obesity. The BMI approximates body mass using a mathematical ratio of weight and height [(weight in kg ÷ height in meters2) or (weight in pounds ÷ height in inches2 x 703)].
A BMI of 30 or more is regarded by most health agencies as the threshold for obesity. A BMI of 40 or more generally qualifies as morbid obesity. However, note that BMI measurements in body-builders and athletes may not be accurate determinants of obesity because the BMI does not distinguish between muscle and fat.

Federal Guidelines for Healthy Weight

  • Underweight. Your BMI is less than 18.5.
  • Ideal Weight for Your Height. Your BMI is between 18.5 and 24.9.
  • Overweight. Your BMI is between 25 and 29.9.
  • Obese. Your BMI is 30 or greater.