Free BMI Calculator for Children
Calculate pediatric BMI for ages 2-20. Get BMI value and percentile category by age and gender.
How It Works
Calculates pediatric BMI for children aged 2-20 using age and gender-specific CDC percentile charts. Unlike adult BMI, children's body composition changes with growth, so this tool provides percentile-based categories rather than fixed ranges. Always consult a pediatrician for clinical assessment.
When to Use It
- Parents monitoring their child's growth between pediatrician visits.
- School nurses screening students for weight-related health concerns.
- Youth sports programs assessing body composition for fitness evaluations.
Frequently Asked Questions
Why is child BMI different from adult?
Children's BMI uses age/gender percentiles because body composition changes during growth. A BMI of 22 may be normal at 16 but overweight at 8. CDC growth charts provide accurate classification.
What do the percentiles mean?
Below 5th is underweight, 5th-85th is healthy, 85th-95th is overweight, above 95th is obese. Percentiles compare your child to the reference population of same age and gender.
Should I rely solely on this tool?
No. This provides estimates for informational purposes. Always consult a pediatrician who considers growth velocity, family history, puberty stage, and overall health.
All calculations happen in your browser. No data is sent to any server.
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