Child Height Predictor Calculator

Estimate a child’s adult height using the heights of both biological parents and a commonly used mid-parental height formula.

Predict your child’s adult height

Enter the child’s sex and the heights of both biological parents to estimate the child’s expected adult height.

Please enter valid heights for both parents. Parent heights must be between 100 and 250 cm or the equivalent range in inches.

Your result

Child
Father’s height
Mother’s height
Predicted adult height
Predicted adult height in inches
Typical prediction range

Step-by-step calculation

Step 1: Convert the parent’s heights
Step 2: Adjust for the child’s sex
Step 3: Add the parental heights
Step 4: Calculate the predicted adult height

What does the result mean?

The predicted adult height is an estimate of how tall a child may be as an adult based primarily on parental height.

Children do not necessarily reach exactly the predicted height. Genetics from the wider family, nutrition, health, hormones, puberty timing, and other factors can influence final adult height.

The result should therefore be viewed as a rough estimate rather than a precise prediction.

How is predicted height calculated?

This calculator uses the mid-parental height method. The method combines the heights of both biological parents and adjusts the calculation based on the child’s sex.

For boys, 13 cm is added to the combined parental height before dividing by two. For girls, 13 cm is subtracted before dividing by two.

The result is commonly interpreted as an estimate around which the child’s adult height may fall, rather than a guaranteed final height.

Child height predictor example

Suppose the father is 180 cm tall and the mother is 165 cm tall.

For a boy:

Predicted height = (180 + 165 + 13) ÷ 2

Predicted height = 358 ÷ 2

Predicted height = 179 cm

For a girl:

Predicted height = (180 + 165 − 13) ÷ 2

Predicted height = 332 ÷ 2

Predicted height = 166 cm

These values are estimates and should not be treated as a guarantee of adult height.

Formula used

Boy:
Predicted adult height = (Father’s height + Mother’s height + 13 cm) ÷ 2

Girl:
Predicted adult height = (Father’s height + Mother’s height − 13 cm) ÷ 2

If your measurements are entered in inches, the calculator converts them to centimeters before applying the formula.

Related calculators

Important: This calculator provides an estimated adult height for general informational purposes only. A child’s actual adult height can differ substantially from the prediction because growth is influenced by many genetic, developmental, nutritional, hormonal, and health-related factors. This calculator is not a medical diagnostic tool and should not be used to assess a child’s health or growth without appropriate professional guidance. If you are concerned about a child’s growth or development, consult a pediatrician or other qualified healthcare professional.