How is a child's adult height estimated?

The most common method is the mid-parental formula: take the average of the parents' heights and add 6.5 cm for a boy or subtract 6.5 cm for a girl. Actual height varies around this by about ±8.5 cm.

How accurate is a height prediction?

The prediction is a statistical estimate. About 95% of children end up within ±8.5 cm of the calculated height. Nutrition, health and individual development affect the outcome.

Is height inherited from the mother or the father?

Height is inherited from both parents. The formula uses the average of both heights. Genes explain about 80% of height, with the rest coming from environmental factors.

Can a child grow taller than the prediction?

Yes. The prediction is an average, and individual variation is large. Good nutrition, enough sleep and good health support growth. Abnormal growth is worth checking at the child health clinic.

Child Height Predictor — Adult Height

Name: Child Height Predictor — Adult Height
Author: Miikka

Estimate your child's adult height from parents' heights. Boy and girl. Free child height prediction calculator.

By Miikka · CalcBrew · Updated Sep 16, 2026

Mother's height: 5 ft 5 in

Father's height: 5 ft 11 in

Child's sex: Boy

5 ft 10 in

Predicted adult height

Predicted adult height	5 ft 10 in
Range (±)	3.3 in
Lower bound	5 ft 7 in
Upper bound	6 ft 2 in

ℹ️ Uses the mid-parental height formula: the average of the parents' heights ± 6.5 cm depending on sex. Actual height varies by ±8.5 cm with genes, nutrition and health. This is a statistical estimate.

This child height predictor estimates a child's future adult height from the parents' heights. You get a prediction along with a realistic range that accounts for genes, nutrition and health affecting the final height.

How the calculator works and what it’s for▾

How the prediction is calculated

The calculator uses the so-called mid-parental formula, the average of the parents' heights, to which 6.5 centimetres is added or subtracted depending on the child's sex.

For boys this sex adjustment is added to the average and for girls it is subtracted, giving a statistical estimate of the likely adult height.

What you enter and what you get

Enter the mother's and father's height in centimetres and select the child's sex.

You get the estimated adult height, its range (±) and a lower and upper bound. The range matters, because real height can differ from the average by several centimetres.

Who it is for

The tool appeals to parents who want a rough idea of their child's future height, whether out of curiosity or to help plan hobbies.

It suits parents of both young children and teenagers, since the prediction is based on the parents' heights rather than the child's current growth.

Good to know

Real height varies by about ±8.5 centimetres depending on genes, nutrition and health, so this is a statistical estimate rather than a guarantee.

Individual factors, such as the timing of the growth spurt, can change the outcome. For closer monitoring, use the growth charts from your child clinic.

🔄 Reviewed June 2026

Frequently asked questions

Cite this calculator

APACalcBrew. (2026). Child Height Predictor — Adult Height. https://calcbrew.com/child-height-predictor

MLA“Child Height Predictor — Adult Height.” CalcBrew, 2026, calcbrew.com/child-height-predictor.

Link to https://calcbrew.com/child-height-predictor. Results are estimates; cite the underlying formula or data source for academic work.

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