Child Adult Height Predictor
Estimate adult height for a child using the Mid-Parental Height formula (Tanner method). Approximate within ±4 inches.
Inputs
Predicted adult height
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Lower range estimate
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Upper range estimate
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In centimeters
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Mid-parental height
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About Child Adult Height Predictor
Accuracy
Mid-parental height predicts adult height within ±4 inches for ~95% of children. Genetics explain about 60-80% of variance — the rest is nutrition, health, sleep, and chance.
When to consult a doctor
If a child is consistently below the 3rd percentile, or growing slower than 2 inches/year between ages 3-puberty, see a pediatric endocrinologist. Early growth-hormone evaluation matters.
Other predictors
Doubling the height at age 2 (boys) or 18 months (girls) is a folk estimate — surprisingly close, but ±4 inches as well. Bone age x-rays give the most precise prediction in older children.