Adult Height Prediction Calculator
Estimate a child's likely adult height based on parental heights using the mid-parental height method.
Enter heights in centimeters.
What this height prediction calculator does
This child height predictor gives a quick estimate of adult height potential using a standard clinical shortcut called the mid-parental height formula. It uses the heights of both parents and adjusts for biological sex. The result is best understood as a range, not a guaranteed final number.
Families often search for terms like adult height calculator, genetic height potential, or target height range. All of these are trying to answer the same practical question: "Given our family pattern, about how tall might this child become?"
How the formula works
Mid-parental height method
- For boys: (Father's height + Mother's height + 13 cm) ÷ 2
- For girls: (Father's height + Mother's height - 13 cm) ÷ 2
After calculating the center estimate, clinicians often use a normal variation band of roughly ±8.5 cm (about ±3.3 inches). This creates a practical target range where adult height is likely to fall.
How to use the calculator correctly
- Select your measurement unit: centimeters or inches.
- Choose the child's sex.
- Enter the mother's and father's current adult heights.
- Click Calculate Predicted Height to view the estimate and likely range.
For best results, use measured heights rather than rounded guesses. Small input changes can shift the estimate.
What affects final adult height beyond genetics?
Genetics is powerful, but it is not the whole story. Growth is influenced by many biological and environmental factors.
- Nutrition: Long-term deficiencies can reduce growth potential.
- Sleep quality: Growth hormone is released in pulses, especially during sleep.
- General health: Chronic illness can affect growth velocity.
- Hormones: Thyroid function, puberty timing, and other endocrine factors matter.
- Physical activity and lifestyle: Supports overall health during growth years.
How accurate is a height prediction calculator?
Think of this as a screening tool, not a diagnosis. It is usually directionally useful for family planning and growth discussions, but it cannot account for every growth variable. Accuracy is generally reasonable at a population level, while individuals can still land outside the predicted range.
If a child is tracking very differently from expected growth chart percentiles, a pediatric growth assessment is more informative than calculator output alone.
When to talk to a pediatrician
Consider medical guidance if you notice major growth concerns, such as:
- Very slow annual height gain compared with peers.
- Crossing down multiple growth percentiles.
- Delayed or unusually early puberty signs.
- Large gap between projected and observed growth trends.
Pediatricians may use growth charts, bone age studies, and endocrine evaluations when appropriate. These provide a much deeper picture than any single online tool.
Quick FAQ
Can this predict height exactly?
No. It estimates probable adult height and a likely range.
Can teens still change a lot in height?
Yes. Puberty timing differs widely, and growth can continue into late adolescence.
Does this work for adults?
The formula is designed for estimating a growing child's future height, not for changing adult height outcomes.
Bottom line
A height prediction calculator is a practical way to estimate genetic height potential quickly. Use it as a guide, pair it with healthy growth habits, and rely on pediatric follow-up for personalized medical interpretation.