Child Height Predictor
Predict your child's adult height using the mid-parental height method.
Enter mother's and father's heights in feet/inches or cm for boys and girls.
Predicting a child’s adult height uses the Mid-Parental Height (MPH) method, which is the most widely used clinical formula. It estimates height based on the genetic contribution of both biological parents.
Formula for boys: Predicted Height = ((Father’s Height + Mother’s Height + 13 cm) / 2) ± 8.5 cm In inches: ((Father’s Height + Mother’s Height + 5 inches) / 2) ± 3.3 inches
Formula for girls: Predicted Height = ((Father’s Height + Mother’s Height − 13 cm) / 2) ± 8.5 cm In inches: ((Father’s Height + Mother’s Height − 5 inches) / 2) ± 3.3 inches
The ±8.5 cm (±3.3 in) range accounts for individual genetic variation — most children fall within this band.
Worked example: Father is 5'10" (70 in), Mother is 5'5" (65 in). Predicting for a son: Predicted Height = (70 + 65 + 5) / 2 = 140 / 2 = 70 inches (5'10") Range: 66.7 in to 73.3 in (5'6.7" to 6'1.3")
Alternative — Bone age method: A more accurate prediction can be made using an X-ray of the child’s left hand/wrist to assess skeletal maturity (bone age). This requires a doctor.
Height doubling rule of thumb: A child’s height at age 2 is roughly half their adult height. A boy’s height at age 2.5 ≈ adult height / 2 A girl’s height at age 2 ≈ adult height / 2
Factors that influence final height:
- Genetics (accounts for ~80% of variation)
- Nutrition, especially calcium and protein during growth
- Sleep (growth hormone is released during deep sleep)
- Overall health and chronic illness history