Child Height Predictor

How to Predict a Child's Future Height

To estimate a child's future adult height, enter the gender and measured height of both parents. Our tool applies the Mid-Parental Height (MPH) method, the standard clinical approach used by pediatricians worldwide. The core calculation follows this genetic principle: $$\text{Target Height} = \frac{H_{father} + H_{mother} \pm 13\text{ cm}}{2}$$ where 13 cm is added for boys and subtracted for girls to account for the average height difference between sexes. The result represents the child's genetic height potential, with a typical prediction range of plus or minus 8 to 10 cm around the midpoint.

Predicting Adult Height

Adult height is predominantly a genetic trait, with heritability estimates ranging from 60% to 80% of total height variability in most populations. The remaining 20% to 40% is shaped by nutrition, sleep quality, chronic illness, hormonal function, and prenatal conditions. A well-nourished child of tall parents is likely to be tall; however, significant nutritional deficits or untreated growth hormone deficiency can meaningfully reduce the genetically projected outcome.

Growth follows a predictable pattern: rapid gains in infancy, a relative plateau from age 2 to puberty, then a pubertal growth spurt. In girls, the peak height velocity typically occurs around ages 11 to 13, with growth largely complete by 15 to 16. In boys, the peak occurs around ages 13 to 15, with most reaching final adult height by 17 to 19. Growth plates (epiphyseal plates) close at the end of puberty, at which point further height gain is not possible.

This calculator gives parents, coaches, and clinicians a validated genetic baseline for a child's expected adult height, useful for tracking development and identifying growth patterns that may warrant a pediatric review.

Useful Tips 💡

• Measure height in the morning: the intervertebral discs expand overnight, making individuals up to 1 to 2 cm taller immediately after waking than later in the day.
• Always use barefoot, standing measurements against a flat wall for both parents and the child to ensure consistency and avoid systematic overestimation.