Height Percentile Calculator for Boys
Enter your son's age and current height. Get his percentile in seconds, using official CDC 2000 growth reference data.
Where does your son fall?
Result
Reference: percentiles for boys at age
| Percentile | Height |
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How this calculator works
This calculator uses the CDC 2000 Growth Charts , the official U.S. clinical reference for children's growth. Specifically, it uses the "stature-for-age" LMS parameters (L, M, S values) that pediatricians and endocrinologists use to compute z-scores and percentiles.
What a percentile actually means
A boy at the 30th percentile is taller than roughly 30% of boys his age, and shorter than roughly 70%. Percentile is descriptive, not a diagnosis. The 5th percentile is not "abnormal" and the 95th percentile is not "healthier."
What matters more than one measurement
The single most important pattern to watch is whether your son tracks along his percentile over time. A boy at the 25th percentile at age 8 who is still around the 25th percentile at age 11 is growing normally, whatever that percentile happens to be. A boy who crosses percentile lines downward over 6-12 months is the pattern that pediatricians want to know about.
Frequently asked questions
Is a low percentile bad?
No. About 10% of healthy boys are below the 10th percentile at any given moment, by definition. Being at a lower percentile doesn't mean anything is medically wrong , it means he's shorter than most boys his age. What matters more is family history (mid-parental height), the trend over time, and whether growth velocity is normal.
What is a "normal" percentile?
There isn't one. Every percentile from the 3rd to the 97th is considered within the range of typical variation. Pediatricians typically flag either the very ends (below the 3rd or above the 97th) or, more importantly, changes in percentile over time.
How accurate is the CDC 2000 data?
The CDC 2000 growth charts are built from large, well-documented U.S. survey samples (mostly NHANES data). They're the official clinical reference in the United States and remain the standard for children ages 2-20. The WHO also publishes international reference charts, which are similar but not identical.
Should I be worried if he crosses percentile lines?
Depends on how much, in which direction, and over what time. Small fluctuations are common. A sustained downward crossing of two or more major percentile lines (for example, dropping from the 50th to below the 10th over a year or two) is the pattern most pediatricians would want to evaluate. Bring the measurements over time to his next appointment.
Does this predict his adult height?
Not by itself. Current percentile is a snapshot, not a prediction. For a rough adult-height estimate, use the family height calculator, which uses both parents' heights (the strongest single predictor).
The height percentile calculator is parent education, not medical advice or diagnosis. Percentile is a descriptive statistic , a low or high percentile is not automatically abnormal. If you have concerns about your son's growth, talk to his pediatrician with the measurements (and, ideally, the trend) in hand. Calculations use CDC 2000 growth reference data for boys 2-18. © 2026 The Growth Path.