Body mass index (BMI) for children and adolescents | Better Health Channel

BMI calculator for children


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).

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The plotted point on the graph is accurate to within .5 of the BMI calculation generated by the calculator.

Based on graphs developed by the National Health Center for Statistics in collaboration with the National Centre for Chronic Disease Prevention and Health Promotion (2000).