About KidGrowthPredictor

KidGrowthPredictor is a set of free calculators for parents: predicting a child's adult height, and finding height, weight, BMI, and head-circumference percentiles. Every number comes from a published growth standard -- the same references a pediatrician uses -- laid out as full tables and charts, not just a single result.

Where the numbers come from

Percentiles for children 2-20 years old use the CDC 2000 Growth Charts (with 2022 revised BMI-for-age extension), published by the Centers for Disease Control and Prevention. Percentiles for infants and toddlers 0-24 months old use the WHO Child Growth Standards (2006), published by the World Health Organization -- the reference recommended for that age range because it describes healthy, breastfed infants rather than a general population. Both are published as LMS parameter tables (three numbers per age that describe the full distribution of a measurement), which this site implements directly rather than approximating from a chart image. The data tables were retrieved on 2026-09-15 and are cited with their source URLs in the reference chart pages.

Adult height prediction uses the mid-parental (Tanner) method, a published rule of thumb from J.M. Tanner's 1970 growth studies, plus a percentile-tracking estimate built on the same CDC data as the percentile calculators. Neither is a substitute for the more detailed Khamis-Roche method, which this site deliberately does not implement -- see the height predictor's FAQ for why.

What this site doesn't do

It doesn't store what you enter, require an account, or diagnose anything. A percentile is a comparison to a reference population, not a judgment about your child's health -- that conversation belongs with your pediatrician, who has your child's history and can see the trend over time, not a single reading.

Corrections

If you're a pediatrician or a researcher and something here doesn't match the published source data, email hello@kidgrowthpredictor.com. Every reference table page cites its source and retrieval date so a correction can be checked directly.