yrs
Enter age between 2 and 20 years.
Decimals OK (e.g. 8.5 = 8 years 6 months)
CDC uses separate charts for boys and girls
ft
Enter feet (1–7).
in
Enter inches (0–11).
Height Percentile
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⚠️ Medical Disclaimer: This calculator is for educational purposes only. Height percentile is a screening tool, not a diagnosis. A single measurement outside typical ranges is not cause for concern on its own. Consult your child's pediatrician to track growth trends over time and interpret results in full clinical context.
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Sources & Methodology
Height percentile calculation based on CDC 2000 height-for-age growth charts, the official standard used by US pediatricians for children and adolescents ages 2-20.
CDC — Clinical Growth Charts for Height-for-Age (2000)
Official CDC 2000 height-for-age growth charts for boys and girls ages 2-20, with LMS parameters used to derive percentile thresholds for this calculator
CDC — Development of the 2000 CDC Growth Charts (Pediatrics)
Peer-reviewed publication describing the statistical methodology, data sources, and LMS parameters used to construct the CDC 2000 growth charts
Methodology: Height in inches converted to cm if needed. Percentile calculated using LMS approximation based on CDC 2000 published median height values by age and sex. Z-score = (height - median) / (SD), where SD is approximated as 4.5% of median. Normal CDF applied to Z-score to produce percentile. Average heights sourced from CDC 50th percentile values. All results are approximate and educational.
⏱ Last reviewed: April 2026
How Child Height Percentile Is Calculated
Height percentile is one of the most important numbers in a child's health record. This height percentile calculator uses CDC 2000 growth chart data — the same charts used in pediatrician offices across the United States. Rather than simply comparing your child to a single average, percentile charts show how your child's height compares to a large nationally representative sample of children the same age and sex.
The Percentile Calculation
Z-score = (Child's Height - Median Height for Age/Sex) / SD
SD (standard deviation) is approximately 4.5% of the median height at each age.
Percentile = normalCDF(Z-score) x 100
Example: Boy age 10, height 56 inches. Median ~54.5 inches, SD ~2.45 in.
Z = (56 - 54.5) / 2.45 = 0.61 → approximately 73rd percentile
Percentile = normalCDF(Z-score) x 100
Example: Boy age 10, height 56 inches. Median ~54.5 inches, SD ~2.45 in.
Z = (56 - 54.5) / 2.45 = 0.61 → approximately 73rd percentile
CDC Average Heights by Age (50th Percentile)
| Age | Boys — Average Height | Girls — Average Height |
|---|---|---|
| 2 years | 34.5 in (87.6 cm) | 34.0 in (86.4 cm) |
| 4 years | 40.3 in (102.3 cm) | 39.8 in (101.1 cm) |
| 6 years | 45.5 in (115.6 cm) | 45.0 in (114.3 cm) |
| 8 years | 50.5 in (128.3 cm) | 50.0 in (127.0 cm) |
| 10 years | 54.5 in (138.4 cm) | 54.3 in (137.9 cm) |
| 12 years | 58.7 in (149.1 cm) | 60.0 in (152.4 cm) |
| 14 years | 64.0 in (162.6 cm) | 63.2 in (160.5 cm) |
| 16 years | 68.0 in (172.7 cm) | 64.0 in (162.6 cm) |
| 18 years | 69.3 in (176.0 cm) | 64.2 in (163.1 cm) |
What Different Percentiles Mean
- Below 5th percentile — Short stature; may be normal with short parents, or may need evaluation
- 5th to 25th percentile — Below average but within normal range; no cause for concern alone
- 25th to 75th percentile — Average range; typical growth
- 75th to 95th percentile — Above average height; normal variation
- Above 95th percentile — Tall stature; usually normal, occasionally warrants monitoring
When to Consult a Pediatrician About Height
A single low or high percentile reading is rarely cause for concern. What matters is the trend over time. Pediatricians track growth at every well-child visit specifically to catch meaningful changes. Consult your pediatrician if your child's height percentile drops 10-15 points or more between visits, if they are consistently below the 5th percentile with no family history of short stature, or if their growth rate appears to have stopped before puberty is complete.
💡 Key Insight: The most important factor in evaluating a child's height is not a single measurement, but the growth velocity — how fast they are growing over time. A child at the 10th percentile who grows consistently at a normal rate is growing normally. A child at the 50th percentile who stops gaining height for 6 months needs evaluation. Always track growth over multiple visits.
Frequently Asked Questions
Height percentile compares your child's height to other children of the same age and sex. A child at the 75th percentile is taller than 75% of children their age and sex. The CDC publishes separate growth charts for boys and girls ages 2-20, which are the US standard for pediatric growth assessment.
Average height for a 10-year-old boy is approximately 54.5 inches (4 ft 6.5 in, 138 cm). For a 10-year-old girl it is approximately 54.3 inches (4 ft 6.3 in, 138 cm). Boys and girls are nearly the same average height at 10, but girls often grow faster in early puberty.
A child is considered tall if their height is at or above the 85th percentile for age and sex on CDC growth charts. Above the 95th percentile may indicate accelerated growth worth monitoring. Very tall stature above the 97th percentile may occasionally have medical causes worth discussing with a pediatrician.
Below the 5th percentile, called short stature, may be normal for children with short parents or late puberty. It can also warrant medical evaluation for growth hormone deficiency, thyroid issues, or other conditions. A pediatrician should evaluate children consistently below the 5th percentile or who show a sudden drop in their percentile ranking.
Height percentile is calculated by comparing a child's height to CDC growth chart data from a nationally representative US sample. A Z-score is calculated using the LMS method with published median values and standard deviations for each age and sex, then converted to a percentile using the standard normal distribution.
Average height for a 5-year-old boy is approximately 43.5 inches (3 ft 7.5 in, 110 cm). For a 5-year-old girl it is approximately 42.9 inches (3 ft 6.9 in, 109 cm). Growth rate during preschool and early school years is approximately 2 to 2.5 inches (5 to 6 cm) per year.
Typical growth rates: infancy 9-12 inches per year, toddlers 3-4 inches per year, school age 2 to 2.5 inches per year, early puberty growth spurt 2.5 to 4 inches per year, peak puberty 3 to 5 inches per year. Growth slows and stops when growth plates close after puberty ends.
Average height for a 13-year-old boy is approximately 61.5 inches (5 ft 1.5 in, 156 cm). For a 13-year-old girl it is approximately 62.0 inches (5 ft 2 in, 157 cm). Girls are often taller than boys at 13 because girls typically begin puberty and their growth spurt 1 to 2 years earlier.
The mid-parental height method: For boys: (Mother's height + Father's height + 5 inches) / 2. For girls: (Mother's height + Father's height - 5 inches) / 2. Typical range is plus or minus 4 inches. A bone age X-ray provides a more accurate prediction when evaluated by a pediatric endocrinologist.
Boys typically stop growing between ages 17 and 21, usually 2 to 3 years after their growth spurt peaks around ages 13 to 15. Growth plates close after puberty ends. The average boy gains 1 to 3 inches after age 16, with most growth complete by age 18.
Girls typically stop growing between ages 14 and 16, about 2 to 3 years after their peak growth spurt around ages 11 to 13. Most girls reach their full adult height by age 15 to 16. Girls complete growth earlier than boys because they begin puberty earlier.
A drop of 10 to 15 percentile points or more between measurements warrants a pediatrician visit. A single small fluctuation may be normal measurement variation. Consistently dropping percentiles can indicate inadequate nutrition, illness, hormonal issues, or other medical conditions. Regular tracking at well-child visits allows early detection.
This calculator uses CDC 2000 growth charts, the US standard for children ages 2-20. WHO growth standards are used internationally. For US children under age 2, WHO standards are recommended. Both are widely accepted references for monitoring child growth.
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