Child Height Predictor

Child Height Predictor Calculator

Wondering how tall your child will grow? Enter age and height to see your child's growth percentile on the official CDC growth charts — plus a predicted adult height based on current growth and both parents' heights.

Based on CDC 2000 growth reference data · Boys & girls ages 2–20 · Free · No sign-up

Try the free child height predictor →

Child's sex
Parental heights (optional — improves the adult height estimate)

Uses CDC 2000 stature-for-age LMS data (ages 2–20). For education only — not medical advice.

Your child's height prediction

Predicted adult height
—
—
Current percentile
—
—
Growth status
—
vs. 3rd–97th percentile band

Growth chart (CDC 2000)

3rd percentile 50th percentile (median) 97th percentile Your child

How the child height predictor works

This height calculator combines two proven clinical methods to estimate how tall your child will grow. Both are used by pediatricians and are based on the same growth charts used in clinics worldwide.

1. Percentile-tracking method (current growth curve)

The calculator places your child's current height on the CDC 2000 stature-for-age growth chart for their sex and exact age, giving a height percentile from 1 to 99. It then assumes the child keeps that percentile into adulthood — a 60th-percentile 6-year-old is projected to finish near the 60th-percentile adult height. This method is most reliable for children who are growing steadily along their curve.

2. Mid-parental height method (genetic target)

The mid-parental height (also called the Tanner or target height formula) estimates the child's genetic height potential from both biological parents:

About two-thirds of children reach adult height within ±8.5 cm of this target. When both parental heights are entered, the calculator blends the genetic target with the percentile projection for the best estimate.

How to use the child height predictor

  1. Select your child's sex — boys and girls use separate CDC growth charts with different height curves.
  2. Enter the age in years and months, then the current height in centimeters or inches.
  3. Add both parents' heights (optional) to include the mid-parental genetic target in the prediction.
  4. Click "Predict adult height" to see the current height percentile, growth status and predicted adult height.
  5. Re-measure every 6 months and run the calculator again — the trend on the growth chart matters more than any single reading.

The estimate becomes more reliable as your child grows: percentile-tracking is most meaningful for children who have stayed on the same growth curve since age 2, while the mid-parental formula can be used at any age.

Understanding growth percentiles

Percentiles tell you how your child compares to thousands of other children of the same age and sex in the CDC reference population:

Children naturally change percentile in the first years of life, and again around puberty, so a single measurement is only a snapshot — tracking height over time on a growth chart is what matters most.

Average height by age (CDC 2000)

Reference values below are the CDC 50th-percentile median heights with the normal 3rd–97th range, in centimeters.

AgeBoys — averageBoys — normal rangeGirls — averageGirls — normal range
2 years86.5 cm79.9 – 93.085.0 cm78.4 – 91.5
3 years95.0 cm88.0 – 102.693.9 cm86.6 – 101.5
4 years102.2 cm94.3 – 110.2100.8 cm92.8 – 109.2
5 years108.9 cm100.1 – 117.5107.7 cm99.1 – 117.0
6 years115.4 cm105.9 – 124.8114.7 cm105.5 – 124.9
7 years121.8 cm111.7 – 132.0121.5 cm111.6 – 132.4
8 years127.9 cm117.3 – 139.0127.6 cm117.1 – 139.1
9 years133.5 cm122.2 – 145.4132.9 cm121.7 – 145.1
10 years138.6 cm126.5 – 151.3138.0 cm125.8 – 151.0
11 years143.5 cm130.6 – 157.0144.0 cm130.5 – 157.8
12 years149.1 cm135.4 – 163.4151.2 cm137.1 – 164.9
13 years156.1 cm141.5 – 171.0157.1 cm144.0 – 170.0
14 years163.8 cm148.2 – 178.5160.4 cm148.0 – 172.8
15 years169.9 cm154.4 – 183.9161.9 cm149.7 – 174.1
16 years173.5 cm158.7 – 187.0162.5 cm150.4 – 174.7
17 years175.3 cm161.2 – 188.6162.9 cm150.7 – 175.1
18 years176.2 cm162.5 – 189.4163.1 cm150.9 – 175.3
19 years176.6 cm163.1 – 189.9163.3 cm151.0 – 175.4
20 years176.8 cm163.3 – 190.2163.3 cm151.1 – 175.5

Notice how girls reach nearly their final height around 14 and boys keep growing into late adolescence — reflected in the 20-year adult averages of about 176.8 cm (5 ft 9.5 in) for boys and 163.3 cm (5 ft 4.3 in) for girls.

What determines a child's height?

Genetics (60–80%)Parental height is the strongest predictor. The mid-parental height formula captures this genetic potential.
NutritionA balanced diet with protein, calcium and vitamin D helps a child reach their growth potential. Malnutrition slows growth.
SleepGrowth hormone is mostly released during deep sleep — children need 8–12 hours depending on age.
Health & activityRegular physical activity supports bone health, while chronic illness or hormone conditions can affect final height.

Growth charts and data sources

This calculator uses the CDC 2000 stature-for-age growth charts — the official LMS parameters for children aged 2 to 20 years, published by the U.S. Centers for Disease Control and Prevention (CDC). The percentile curves shown in the chart above are the CDC's own smoothed values, and monthly values are linearly interpolated exactly as the CDC recommends. You can download the raw reference data from the CDC growth chart data files.

Frequently asked questions about child height prediction

How accurate is the child height predictor?

The mid-parental (Tanner) method predicts adult height within about 8.5 cm (one standard deviation) for roughly two thirds of children. Percentile-tracking predictions are most accurate for healthy children who stay on their growth curve. No height predictor is exact — genetics, nutrition, sleep and health all influence the final result.

How tall will my child be?

Your child's adult height is estimated two ways: the mid-parental height formula, which averages both parents' heights, and the percentile-tracking method, which projects the child's current CDC growth percentile to the adult median at age 20.

What is mid-parental height and how is it calculated?

Mid-parental height is the genetic height target based on both biological parents. For boys: (father's height + mother's height + 13 cm) ÷ 2. For girls: (father's height + mother's height − 13 cm) ÷ 2. The typical range around the target is ±8.5 cm.

What is a normal height percentile for a child?

The 3rd to 97th percentile is considered the normal range on CDC growth charts. Being below the 3rd or above the 97th percentile, or crossing two major percentile lines, is a reason to speak with a pediatrician.

At what age do boys and girls stop growing?

Girls usually stop growing about 2 years after their first period, typically around age 14–15. Boys keep growing into late adolescence and typically reach final height around ages 17–19.

Can nutrition and sleep make a child taller?

A balanced diet, adequate protein, calcium and vitamin D, regular physical activity and 8–12 hours of sleep help a child reach their genetic height potential. They cannot exceed the genetic target, but poor nutrition or chronic illness can reduce it.

Is my child too short or too tall?

This calculator compares your child's height to the CDC 2000 reference for the same age and sex. Most children are within the normal 3rd–97th percentile band. If your child is outside it, or their growth slows unexpectedly, consult a pediatrician.

What growth chart data does the calculator use?

The CDC 2000 stature-for-age growth charts — official LMS parameters for children aged 2 to 20 years, with linear interpolation between monthly values as recommended by the CDC. Percentiles shown are the CDC's smoothed values.

How do I measure my child's height correctly?

Measure without shoes, standing straight against a flat wall, heels together, looking straight ahead. Use a flat object on top of the head and mark the wall. Measure in centimeters (or inches) to the nearest 0.1 cm — the calculator supports both units.

Do children always grow to match their parents' height?

No. Mid-parental height is a statistical average — individual children often end up taller or shorter than the target. Growth is influenced by genetics (about 60–80%), nutrition, sleep, physical activity, and overall health during childhood.

What is the best age to predict my child's height?

Percentile-tracking predictions are most stable between ages 2 and 9, before the growth spurt begins — a child who has stayed on the same curve since age 2 is likely to stay on it. The mid-parental (genetic) method can be used at any age, including before a child is born.

Can I predict height using only the parents' heights?

Yes. The mid-parental (Tanner) formula estimates the genetic height target from both parents: boys (father + mother + 13) ÷ 2, girls (father + mother − 13) ÷ 2. About two-thirds of children finish within ±8.5 cm of that target — a useful estimate even without the child's current height.

How much taller do boys grow after 14?

On the CDC charts, boys average 163.8 cm at 14 and 176.8 cm at 20 — about 13 cm of additional growth, mostly before age 16. Girls average 160.4 cm at 14 and 163.3 cm at 20 — only about 3 cm, because their growth spurt happens earlier.

Is 140 cm tall for a 10-year-old?

Very close to average. The CDC median height for a 10-year-old boy is 138.6 cm and for a girl 138.0 cm, so 140 cm sits around the 55th percentile — comfortably within the normal 3rd–97th range for both sexes.

Do boys stop growing at 18?

Most boys reach their final height between 17 and 19, and some keep growing into their early 20s until the growth plates fuse. The CDC 2000 charts show boys average 176.2 cm at 18 and only about half a centimeter more by 20.

How often should I track my child's height?

Measure every 6 months and compare the percentile on the growth chart. Occasional jumps or dips are normal, but consistently crossing two major percentile lines downward — or sitting below the 3rd percentile — is a reason to see a pediatrician.

Disclaimer: This child height predictor is for educational and informational purposes only and does not constitute medical advice. Growth is influenced by genetics, nutrition, and health. Always consult a pediatrician or healthcare professional about your child's growth.