Child BMI Calculator
Children's Health Centre by checkit.health
Why child BMI uses percentiles
Children’s body composition changes rapidly as they grow, so a fixed adult BMI cut-off doesn’t work. Instead, a child’s BMI is compared to other children of the same age and sex and expressed as a percentile.
What do the percentiles mean?
Common categories (CDC): under 5th = underweight, 5th–84th = healthy weight, 85th–94th = overweight, 95th+ = obesity. WHO uses similar bands. Your clinician interprets these alongside growth history.
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Educational use only. checkit.health calculators provide general information and are not a medical diagnosis or a substitute for professional advice. Always talk to a qualified healthcare professional about your health, symptoms or before making changes to medication, diet or exercise.
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