The child height predictor estimates your child's adult height using the mid-parental height formula — a validated pediatric method based on both parent heights. Results include a normal range of ±2 inches (5cm) that accounts for typical genetic variation.
Child Adult Height Predictor
How to Predict Your Child's Adult Height
The mid-parental height method is the most widely used pediatric formula for predicting adult height. This child height predictor applies the formula and shows a realistic range based on normal genetic variation.
The Formula
For boys: add both parent heights, add 5 inches (13cm), divide by 2. For girls: add both parent heights, subtract 5 inches (13cm), divide by 2. The ±2 inch (5cm) range accounts for about 95% of children with no underlying growth disorders.
When to See a Doctor
If your child is consistently below the 3rd percentile on growth charts, growing less than 2 inches per year after age 3, or has lost height percentile ranking, consult a pediatrician. A bone age X-ray can provide a more accurate prediction and rule out growth hormone issues or other conditions.
Frequently Asked Questions
Is this child height predictor free?
Yes, completely free. All calculations run locally in your browser.
How accurate is the mid-parental height prediction?
The mid-parental height formula predicts adult height within ±2 inches (5cm) for about 95% of children. It does not account for nutrition, health conditions, or early/late puberty onset. Children with growth concerns should be evaluated by a pediatrician who can assess bone age via wrist X-ray for a more precise prediction.
What is the mid-parental height formula?
For boys: (Father's height + Mother's height + 5 inches) ÷ 2. For girls: (Father's height + Mother's height - 5 inches) ÷ 2. This gives the target adult height. The normal range is ±2 inches (5cm) around this target.
At what age do children stop growing?
Girls typically stop growing 2 years after their first period, usually at ages 14–16. Boys usually stop growing between ages 16–18. However, some boys continue gaining height until age 20–21. Final adult height is reached when growth plates (epiphyseal plates) close.
Does the child's current height affect the prediction?
The mid-parental formula is based solely on parent heights and is a genetic target. The child's current height percentile can help assess whether they're tracking toward that target. A child growing consistently at the 25th percentile will likely end up near the 25th percentile of the predicted range.