Child Adult Height Prediction Calculator

The MPH formula provides a 95% prediction interval of ±8.5 cm (about ±3.3 inches). This means that 95% of children born to those parents will reach an adult height within that range. Individual variation is real — genetics explains ~70–80% of height, with nutrition, sleep, stress, and health making up the remainder.

For boys: predicted height = (father's height + mother's height + 13 cm) ÷ 2. For girls: predicted height = (father's height + mother's height − 13 cm) ÷ 2. The 13 cm correction accounts for the average height difference between adult men and women. This is the Tanner-Whitehouse formula, widely used in clinical pediatrics.

It means the normal variation went in their favor! Children can deviate from the MPH prediction due to optimal nutrition, plenty of sleep, or simply genetic expression that favored height. Conversely, children who are consistently shorter than their predicted range (especially if their growth curve has decelerated) should be evaluated by a pediatrician.

Height growth ends when the growth plates (epiphyseal plates) in the long bones fuse — typically by age 16–17 in girls and 18–19 in boys, though there is considerable variation. Early puberty generally predicts earlier fusion and may reduce final adult height; late puberty may allow additional height years.

Growth hormone therapy in children with GH deficiency can significantly increase final adult height, potentially adding several centimeters beyond the MPH prediction. In typically developing children, the clinical guidelines do not support GH use purely for height augmentation.

Focus on what is controllable: adequate sleep (GH is secreted primarily during deep sleep), balanced nutrition with sufficient protein and calcium, regular physical activity, healthy body weight, and treating any chronic illnesses promptly. Avoid smoking around children — it's associated with reduced height.