CDC growth charts · Fels Longitudinal Study · Tanner 1970

How tall will they actually be?

PredictHeight estimates adult stature from mother, father, and the child’s own growth curve — then tells you what sleep, food, and training can (and cannot) change.

~80% genetics
±5 cm typical KR error
0 cm from stretching bones

Growth forecast

US Metric

The kid

Boy Girl

Age, years Months

Height, feet Inches

Weight, lb optional — unlocks Khamis–Roche

The genetics

Mom, feet Inches

Dad, feet Inches

Weight lets us run Khamis–Roche, the Fels Study method used when you do not have a bone-age X-ray. Leave it blank and we still blend CDC percentile with mid-parental height.

1. CDC percentile

We place the child on the official U.S. stature-for-age chart (ages 2–20) using LMS z-scores, then project that percentile to age 20.

2. Parental genetics

Tanner’s mid-parental formula and Luo’s 1998 regression. Heritability of height is about 80% in well-fed populations.

3. Khamis–Roche

When weight is entered (ages 4–17.5), we use the 1995-corrected coefficients from Pediatrics. Typical 90% error: about ±5 cm.