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.
These tools are free forever. SARA takes it further.
SARA is your AI agent on WhatsApp: answers customers, takes bookings, follows up — 24/7, automatically. Try it free for 14 days.
Start your free 14-day trial →