Adult-height prediction
A height predictor that shows ranges, not promises
GrowTall explores adult-height estimates using established methods and the information already in your growth profile — and always presents the result as a range.
GrowTall predicts adult height using two established methods — the mid-parental target height and the Khamis-Roche model — and always shows results as a range, because genetics and development make exact prediction impossible.
Two validated methods
GrowTall's estimates come from published, widely used pediatric references — not black-box formulas:
- Mid-parental target height — a genetic corridor calculated from the biological parents' heights, with a sex adjustment for boys and girls.
- Khamis-Roche model — a validated statistical model that adds the child's age, current height and weight to sharpen the estimate, with no bone-age X-ray required.
Together they answer the question people actually ask — how tall could you become? — with an honest corridor instead of a single number.
Why ranges are the honest format
Adult height is a complex, polygenic trait shaped by genetics, nutrition, sleep, health and puberty timing. Even the best prediction models carry a natural margin of several centimeters. Any app that promises an exact final height is overselling.
GrowTall shows the estimated range on a visual scale — for example, 165–178 cm with a target marker — so you can see where today's trajectory sits inside the corridor.
What makes an estimate better
- Consistent measurements — a clean, 60–90-day measurement history reduces noise.
- Parental heights entered — both methods use them; accurate values sharpen the corridor.
- More growth behind you — estimates naturally firm up as a child moves through middle childhood and puberty.
Estimates update automatically as new measurements arrive. See the Khamis-Roche method and mid-parental height guides for the details.
What a height predictor cannot do
No predictor can account for everything — individual development creates real variation, and no app can override genetics. GrowTall will never sell you a way to "beat" your range, and estimates are never a diagnosis. If growth ever looks unusual — dropping across percentile channels, or unusually slow velocity — that is a conversation for a pediatrician, and GrowTall's summary report is built to help with exactly that discussion.
Common questions
How accurate is the height prediction?
Both methods are established in pediatric practice, but all height predictions carry natural variation of several centimeters. That is why GrowTall shows a corridor (for example 165–178 cm) rather than a single guaranteed number.
Does the prediction need a bone-age X-ray?
No. The Khamis-Roche method was developed specifically to predict adult stature without skeletal-age imaging, using age, height, weight and parental heights instead.
When should we re-check the estimate?
Whenever a new measurement is added. Estimates update automatically, and they generally become more stable through middle childhood and puberty.
Are predictions included in the free version?
Adult-height estimates, including Khamis-Roche and the mid-parental target range, are part of GrowTall Plus. Core tracking stays free.
Explore your growth, honestly.
Evidence-based adult-height estimates, growth curves and percentiles — with ranges you can trust.