Child Height Predictor
Enter both parents' heights and the child's gender — get an estimated adult height and confidence interval. Based on the standard mid-parental height formula.
- Enough sleep: Growth hormone secretes during deep sleep — 9–10 hr for elementary, 8–9 hr for teens.
- Balanced nutrition: Protein (meat/fish/beans), calcium (milk/cheese), vitamin D (sun/salmon).
- Jumping exercise: Jump rope, basketball, volleyball — vertical-axis loading activates growth plates.
- Manage stress: Chronic stress suppresses growth hormone.
How to Use
Enter father's and mother's heights in cm (range 140–210 cm).
Boy or girl. Same parents — male children are predicted ~13 cm taller on average.
Estimated adult height plus a 95% confidence interval (±8.5 cm) is shown. Predictions tend slightly toward the population mean (regression), and environment (nutrition, sleep, exercise) can shift the actual ±5 cm further.
FAQ
What is the mid-parental height (MPH) formula?
The standard formula in pediatrics/endocrinology to estimate adult height. Boys: (father + mother + 13) / 2 cm. Girls: (father + mother − 13) / 2 cm. The 13 cm adjusts for the average male–female adult height difference. Proposed by Tanner et al. in 1970; widely used in clinical practice.
What does the 95% CI of ±8.5 cm mean?
The prediction has a standard deviation of ~4 cm, so the actual adult height falls within ±8.5 cm of the prediction 95% of the time. A '172 cm prediction' means roughly 163.5–180.5 cm. Treat it as a range, not a point.
How accurate is it?
Height is ~70–80% genetic and 20–30% environmental. Malnutrition, chronic illness, lack of exercise, or poor sleep can reduce achieved height by 5–10 cm. With ideal conditions, children can exceed the parental average by ~5 cm. Countries like Korea and Japan continue to see generational height increases due to better nutrition.
What affects growth?
①Nutrition: enough protein, calcium, vitamin D. ②Sleep: growth hormone secretes during deep sleep — 9–10 hr for primary kids, 8–9 hr for teens. ③Exercise: jumping, running, basketball, jump-rope. ④Stress management. ⑤Early detection of chronic conditions. Pre-puberty management is most effective.
Can they grow more after puberty?
Girls: 5–8 cm after menarche (typically until age 16–17). Boys: 5–10 cm during 2–3 years after voice break (typically until 18–19). Once growth plates close (visible on X-ray), further growth is minimal. After age 22, additional growth is very rare.
Should I take this as a final answer?
No — this is a statistical estimate. Individual variation is large and this does NOT replace medical diagnosis. If you suspect growth delay or excessive growth, consult a pediatrician or pediatric endocrinologist.
Is my input sent to a server?
No. All computation runs in your browser; inputs are never sent over the network.
