How to Calculate your BMI

The formula for calculating BMI uses weight in kilograms and height in metres:

BMI (kg/m2) = Weight (kg) ÷ Height (m) 2.

It can also be calculated using weight in pounds and height in inches:

BMI (lb/in2) = Weight (lb) ÷ Height (in) 2 x 703.

Online calculators that automatically do the computations from an entered height and weight are a convenient method of determining BMI.

Definitions of overweight and obesity

Over 50 healthcare organisations around the world, use the same BMI standards to define adult overweight and obesity.

Definition BMI
Overweight: 25-29.9
Obese: 30-39.9
Morbidly Obese: 40+