Last updated: March 2, 2026 by Dr. David Park

Understanding Baby Growth Percentiles

Formula

Growth percentiles compare your baby's measurements to a reference population of healthy children of the same age and sex. The WHO growth standards, based on data from six countries, are used for children 0-5 years old.

A baby at the 50th percentile for weight is heavier than 50% of babies and lighter than 50%. Percentiles between the 5th and 95th are generally considered normal. Tracking trends over time is more important than any single measurement.

Common use cases:

  • Pediatric wellness checkups
  • Monitoring infant development
  • Identifying growth concerns early

Frequently Asked Questions

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Dr. David Park

Applied Mathematician, PhD Mathematics

David holds a PhD in Applied Mathematics from MIT. He has published research on numerical methods and computational algorithms used in engineering and scientific calculators.

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