How Tall Will My Child Be?

It's a common question parents ask. "How tall will my child be? Will they be tall enough to play basketball? What's the average height for a boy or girl that is my child's age?" These questions can all be answered with a couple easy questions and the help of some statistics provided by the CDC.

Height Calculator

Enter your child's sex, height (in centimeters), and age (in months) in the boxes below. Press enter or click "Update" to update the boxes on the right. The "percentile" box tells you how tall your child is relative to other children his/her age. (For example, a value of 85% means your child is currently taller than about 85% of other children his/her age.) The "estimated adult height" box predicts your child's height.

Height Calculator

How Does the Height Calculator Work?

The height calculator uses data from the CDC to compare your child's height to other children his/her age. Once your child's height percentile is known, that value is assumed to stay constant through adulthood. Your child's height is then predicted to be at the same percentile at the oldest age in the CDC data, 240 months, or 20 years. Of course, if your child just finished an early growth spurt, then his/her estimated adult height may be greater than his actual adult height. The opposite can also be true.


This calculator is for amusement only. Estimates may be wildly inaccurate.


Photo of the "Troops of the Eight nations alliance 1900" by Anonymous