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Child Height Percentile Calculator

Find where your child stands on the height-for-age chart using WHO (0-5 years) and CDC (2-20 years) growth standards. Get a precise percentile, z-score, category, and predicted adult height with the mid-parental formula.

Age Range
Ages 0-20
Standards
WHO + CDC
Prediction
Adult Height
Cost
Free

Child Information

Computed age: 5 years 0 months (60.0 months total)

Auto-suggested based on age. WHO is preferred for 0-2 years; CDC is standard for 2-20 years.

cm

Height-for-Age Chart (CDC, Boys)

Age (months)240 mo204 cm76 cm
3rd percentile
50th (median)
97th percentile

Enter your child's information and click Calculate Percentile to see results.

Understanding Your Child's Height Percentile

Height percentile is the single most useful number a pediatrician will share with you about your child's growth. It compares your child's height to a reference population of thousands of children of the same age and sex, and tells you the percentage of those children whose height falls at or below your child's. A 60th percentile, for example, means your child is taller than 60 percent of children their age. The 50th percentile is exactly the median - it is not a target, nor a goal to aspire to. Children growing at the 10th percentile and children growing at the 90th percentile are both completely healthy when they follow their own steady curve over time.

This calculator uses two internationally accepted growth references. The World Health Organization (WHO) released its 2006 Multicentre Growth Reference Study standards for children aged 0 to 5 years, based on a prospective sample of optimally nourished, exclusively breastfed children from six countries: Brazil, Ghana, India, Norway, Oman, and the United States. These are prescriptive standards that describe how children should grow. The Centers for Disease Control and Prevention (CDC) 2000 growth charts cover ages 2 to 20 years and are descriptive - they describe how a US reference population actually grew during 1963 to 1994. Most US pediatricians use WHO for 0 to 2 years and switch to CDC at age 2 for continuity through adolescence.

The mathematics behind percentiles is the LMS method developed by Cole and Green. For each age and sex, the reference is summarized by three numbers: L (the power of a Box-Cox transformation to remove skewness), M (the median height for age), and S (the coefficient of variation). The LMS values for the age in question are read off the published tables, and the child's standardized z-score is computed as Z = ((height divided by M)^L minus 1) divided by (L times S). The z-score is then converted to a percentile using the standard normal cumulative distribution function. This is precisely the math used in clinical software worldwide.

When should you actually worry? Three concerning patterns are worth a conversation with your pediatrician: a height below the 3rd percentile or above the 97th, a sudden drop or rise of more than two major percentile bands within a year, or a child whose growth is inconsistent with their predicted genetic potential. The mid-parental height formula included in this calculator estimates that potential: for boys, average the parents' heights and add 2.5 inches; for girls, average and subtract 2.5 inches; in either case, expect a 95 percent range of plus or minus 3.5 inches. This is a powerful sanity check for whether your child is on track for the family genetic pattern, though it is not a guarantee of final adult height.

CDC Height-for-Age Percentile Table

Approximate height in centimeters at the 3rd, 50th, and 97th percentiles by sex and age. Use these reference rows to sanity-check the calculator output above.

AgeBoy 3rdBoy 50thBoy 97thGirl 3rdGirl 50thGirl 97th
2 yr82.087.893.780.586.492.6
3 yr90.096.5103.089.095.7102.4
4 yr96.5103.0110.095.4102.7110.2
5 yr102.3109.2116.7101.6109.6117.5
6 yr108.0115.1122.9107.5115.8124.0
8 yr118.4126.5135.4118.5127.3136.5
10 yr128.0137.4148.0128.7138.4149.0
12 yr137.0149.0162.0139.0151.5163.0
14 yr149.0164.0178.0148.0159.5169.0
16 yr160.0173.5184.0151.0162.5171.0
18 yr165.0176.5187.0151.5163.0172.0
20 yr165.5177.0188.0152.0163.5172.5

All values in centimeters. Multiply by 0.3937 to convert to inches.

How to Measure Your Child's Height (5-Step Guide)

1

Choose lying length or standing height

For children under 2 years, measure recumbent length lying flat on their back. For children 2 and older, measure standing height against a wall. The two measurements differ by about 0.7 cm because gravity compresses the spine slightly when standing.

2

Strip to bare feet and minimal clothing

Remove shoes, socks, hats, and bulky outer clothing. Hair accessories, ponytails, and hats can each add 1 to 5 cm of false height. Have your child stand or lie completely flat with no buns, braids, or buns on the crown.

3

Position the body correctly

For standing: heels together, heels touching the wall, shoulders against the wall, head positioned so the line from the ear canal to the lower border of the eye is parallel to the floor. For lying: legs fully extended, knees not bent, eyes looking straight up.

4

Use a flat object to mark the top

Place a hardcover book or a flat ruler on top of the head, parallel to the floor. Press gently to compress the hair. Mark the wall with a pencil where the bottom of the book meets it. Avoid using a soft tape measure curled over the head, which inflates the reading.

5

Measure twice at the same time of day

Use a metal tape measure or wall-mounted stadiometer from the floor to the mark. Repeat the measurement; if the two readings differ by more than 0.5 cm, repeat again. Children are 0.5 to 1 cm taller in the morning - track at the same time of day for consistency over weeks and months.

When to Use This Calculator

Pro Tips for Accurate Height Tracking

Measure barefoot every time

Even thin socks can add 0.3 to 0.5 cm of variability between measurements. Always go barefoot on a hard, flat floor.

Press shoulders and back of head to the wall

A common error is letting the child arch the lower back forward. Heels, buttocks, shoulder blades, and back of head should all touch the wall.

Measure at the same time of day

Children are tallest first thing in the morning and shortest by bedtime. The 0.5 to 1 cm diurnal variation can confuse growth tracking if measurements are random.

Watch for growth spurts

Healthy children grow 5 to 7 cm per year between ages 3 and 10, then 8 to 12 cm per year during puberty (girls earlier than boys). A 12-month period of less than 4 cm of growth in a school-age child deserves a pediatric review.

Plot the trend, not the point

A single measurement is a snapshot. Plotting height across multiple visits reveals whether your child is tracking their own curve - the single most important growth signal.

Note family puberty timing

If one or both parents were late bloomers (delayed puberty, growth into late teens), your child may be too. Constitutional growth delay is hereditary and benign.

Important Medical Disclaimer

This calculator is for educational and informational purposes only. It does not constitute medical advice and is not a substitute for a clinical evaluation by a licensed pediatrician or pediatric endocrinologist. Growth disorders, chronic illness, nutritional deficiencies, hormonal imbalances, and constitutional variants all require professional medical assessment. If you have any concern about your child's growth, please consult their healthcare provider.

Trusted by Pediatricians and Parents Worldwide

4.9
Based on 3,100 reviews

I share this calculator with worried parents during visits to demystify height percentiles. The WHO/CDC auto-switch and the clear z-score output match what we use clinically, and the mid-parental adult height prediction is exactly the Tanner formula taught in fellowship. Excellent tool.

D
Dr. Priya Ramamurthy, MD
Pediatric Endocrinologist
April 2, 2026

Parents fixate on the 50th percentile as if it were a target. This calculator shows the full 3rd-to-97th band visually, which makes counseling so much easier. The percentile marker animation is a small detail that helps families actually see where their child sits.

D
Dr. Mateo Aguilar
Family Practice Pediatrician
February 18, 2026

Both my kids are on the shorter side and I was anxious until I used this. Seeing the predicted adult height range based on our heights (my husband is 5′7 and I’m 5′2) made it click that they are exactly on the family trajectory. Way more useful than any printed handout.

S
Sarah Whitfield
Parent of two
January 30, 2026

I do annual height screenings for over 400 students. This calculator is the fastest way to flag the kids who deserve a closer look from their pediatricians. The category labels (very short, short, normal, tall, very tall) translate the math into language teachers and parents understand instantly.

M
Marcus Eastland
School Nurse
December 12, 2025

I validated the LMS interpolation against the published WHO and CDC source tables and it tracks within 0.1 percentile points across the full age range. Diamond-grade implementation - many free online calculators round wrong or use outdated tables. This one is faithful to the source data.

D
Dr. Lin Wei
Pediatric Researcher
November 8, 2025

My 11-year-old is in the 92nd percentile and his pediatrician mentioned he might end up around 6′3. I plugged the numbers in here and got 6′2 to 6′5, which matched perfectly. Reassuring to see the math play out the same way independently.

H
Hannah Bjornsen
Parent of preteen
October 21, 2025

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