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.

Manage your wellness center with WellnessOS
Discover SOLO SARA — The AI WhatsApp assistant for freelancers at €9.90/month

All calculations happen in your browser. No data is sent to any server.