Child Height Predictor

Yearly height table: compare values alongside the chart

The yearly height table makes it easier to read and compare numerical values for every age from 2 to 20. Your results show the P3, P50 and P97 CDC stature references for the selected sex, with optional same-percentile illustration values only from the child’s current age onward. Hovering or focusing a row highlights that age on the chart and shows its values. The separate measurements table contains only heights you entered. These tables describe reference values and measurements, not annual height goals or guaranteed growth.

This public table shows population medians for orientation. Complete the calculator to see percentile ranges, entered measurements and the optional illustration together. A median is a reference value, not a recommended height.

How to estimate a child’s adult height

This free height calculator uses the mid-parental method, also called the target-height or Tanner method. It combines the measured heights of the biological parents with a conventional adjustment for the child’s sex. The answer is a starting point for discussing family height patterns, rather than a forecast of exactly how tall a child will become.

How to use the calculator

1. Measure the biological father’s and mother’s adult heights without shoes. Use recent measurements when available rather than an approximate height remembered from years ago.
2. Select centimeters or inches and enter both heights in that unit. For example, 5 feet 10 inches is 70 inches; do not enter 5.10 as a decimal height.
3. Confirm the child’s sex and calculate the family target. Optionally add the child’s age, measured height and previous measurements for the CDC chart. Changing any input requires a new calculation.

Mid-parental height formula

The adjustment is inside the parentheses: 13 cm is added or subtracted before dividing by two. Equivalently, calculate the parents’ average height and then add 6.5 cm for a boy or subtract 6.5 cm for a girl. The same metric formula is used when you enter inches, so changing units does not select a different method.

Worked example: father 178 cm, mother 165 cm

For a boy: (178 + 165 + 13) ÷ 2 = 178 cm. The conventional target range is 169.5–186.5 cm.

For a girl with the same parental heights: (178 + 165 − 13) ÷ 2 = 165 cm. The conventional target range is 156.5–173.5 cm.

What does the target range mean?

The calculator shows the target plus and minus 8.5 cm, following the clinical reference linked below. It describes a conventional family-based range, not an individual probability forecast. Published methods can use different adjustments or ranges. Real adult height can fall outside this interval, and the decimal shown in the result is calculation precision, not prediction accuracy.

Can a chart show future height each year?

The optional chart uses the CDC 2000 stature-for-age reference for ages 2–20. Enter the child’s age in completed years plus additional months and their measured standing height. Previous measurements show observed growth. The shaded P3–P97 band describes the reference population; it is not the child’s family target range.

The dashed scenario keeps the current height z-score constant at later ages. For example, a child at the reference median would follow the median curve only if that percentile stayed the same. The age-20 scenario can be compared with the conventional adult family range as a discussion aid. It is not a validated personal adult-height prediction and cannot account for puberty timing, illness or changes in growth velocity. The family target calculation remains based on parental heights and sex.

LMS parameters are linearly interpolated between the surrounding CDC ages. Percentiles come from the corresponding z-score; yearly reference curves and the scenario use the inverse LMS equation. Heights entered in inches are converted to centimeters before calculation.

What this height predictor cannot tell you

The family target calculation does not use the child’s age or current height. The optional chart compares entered heights with the CDC reference and can illustrate a constant-percentile scenario. Neither method evaluates puberty, bone age, growth remaining or the need for treatment. Nutrition, health conditions and puberty timing can affect final height.

If you are concerned about growth, take repeated measurements and discuss them with a pediatrician. A clinician can consider the growth chart and medical history and decide whether further assessment is appropriate. Do not use a low or high estimate on its own to label a child’s growth or start supplements or medication.

Questions about child height prediction

Sources and method

• Formula and conventional ±8.5 cm range: Children’s Mercy — Evaluating Growth Failure.
• Background for families: American Academy of Pediatrics — Predicting a Child’s Adult Height.
• Yearly stature references, percentiles and LMS equations: Centers for Disease Control and Prevention — CDC Growth Charts Data Files.
• Growth assessment: Pediatric Endocrine Society — Short Stature: A Guide for Families.

Content updated October 8, 2026. Educational reference; not a personalized medical assessment.

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