Body mass index calculator for children and teenagers

This calculator measures body mass index (BMI), which is a measure of body fat. It is only an approximate measure of the best weight for your health. The calculator can be used for anyone from two to 20 years of age.

Please note:

• Always see your doctor if you are concerned about your child's growth.
• The BMI is used to assess whether a person is underweight, normal weight, overweight or obese.
• As children grow, their amount of body fat changes and so will their BMI. That's why a BMI calculation for a child or adolescent must take into account their age and gender (we do this using percentile charts).

Also note, the Better Health Channel has a Body mass index calculator for adults.