Child Growth Calculator

This evidence-based calculator determines your child's height, weight, and BMI percentiles based on age and gender. Use this tool to track growth patterns, compare to national standards, and understand your child's development.

Medical Disclaimer: This tool provides general educational estimates. Consult your pediatrician for personalized growth tracking.

Contents

📘 Related Guide

Want to learn more about growth prediction accuracy and methods? Explore our height prediction methods analysis →

How to Use This Calculator

Follow these steps to calculate your child's growth percentiles based on CDC and WHO growth standards:

  1. Enter gender: Different standards apply to boys and girls.
  2. Input age: Enter years and months separately for precise calculations.
  3. Choose measurement units: Select metric (cm/kg) or imperial (in/lbs).
  4. Enter height and weight: Use recent, accurate measurements.
  5. View results: See percentiles and interpretations for height, weight, and BMI.

Understanding Your Results

  • Percentile Ranking: Shows where your child stands compared to peers of the same age and gender.
  • Growth Charts: Visual representations of your child's measurements relative to standard growth curves.
  • Clinical Interpretations: Explanations of what the percentiles mean in practical terms.

Results are based on CDC growth charts for children 2-20 years and WHO growth standards for children under 5. This tool helps monitor growth patterns over time, but should not replace regular pediatric check-ups.

Frequently Asked Questions

What is a growth percentile?

A growth percentile indicates how your child's measurements compare to other children of the same age and gender. For example, if your child is in the 75th percentile for height, it means they are taller than 75% of children their age. Percentiles help pediatricians track whether children are growing in a healthy pattern relative to their peers.

How often should I check my child's growth percentile?

Most pediatricians measure growth at every well-child visit, which typically occurs more frequently during infancy (2-4 months) and spaces out to annual visits for older children. For home monitoring, checking every 3-6 months is reasonable. What's most important is tracking the pattern over time rather than focusing on a single measurement.

Which growth chart should I use — CDC or WHO?

In the United States, the American Academy of Pediatrics recommends using WHO growth standards for all children under 2 years of age and CDC growth charts for children 2-20 years old. The WHO charts better represent optimal growth for younger children, while CDC charts better reflect the U.S. population for older children. This calculator automatically applies the appropriate standards based on your child's age.

Should I be concerned if my child is in a low percentile?

Not necessarily. What's most important is that your child follows a consistent growth curve over time, not their specific percentile. Some children are naturally smaller or larger based on genetics. However, significant drops or jumps across percentile lines (crossing two or more major percentile lines) may warrant discussion with your pediatrician, as might consistently being below the 3rd or above the 97th percentile.

How accurate are online growth calculators?

Online calculators like this one use standard growth data from reliable sources like the CDC and WHO, but they provide estimates rather than clinical assessments. Factors affecting accuracy include measurement precision, data input accuracy, and individual variations not captured by standardized charts. Always discuss results with a healthcare provider, especially if you have concerns about your child's growth.