Free height calculator for parents
How tall will my child be?
Enter each parent’s height, and whether your child is a boy or a girl. You’ll see the range they’re likely to finish in.
Work out your child’s range
It runs in your browser. Nothing you type is sent or saved.
It’s a guide, not a promise. A few people finish outside their range.
How it works
This is the Tanner method, from 1970. It needs three things: the mother’s height, the father’s height, and boy or girl.
Add the mother’s and father’s heights and halve the total. That’s the middle of the parents’ heights.
Boys usually end up about 6.5 cm taller than that, girls about 6.5 cm shorter. That’s about 2½ in. It’s because boys and girls grow differently.
Most children finish within 8.5 cm of their middle, or about 3½ in. So their range runs 8.5 cm either side of it.
Say the mother is 165 cm and the father is 181 cm. Half their total is 173 cm. A girl’s middle is about 167 cm, and her range is 158 to 175 cm. In feet and inches, that’s 5 ft 2 in to 5 ft 9 in.
It doesn’t use your child’s age, height today or weight, so the range is wide. See the full method.
Want a narrower range?
For a narrower range, Plus uses the Khamis–Roche method. It takes what you’ve already given and adds your child’s age, their height today and their weight today.
Centile Plus is for ages 13 to 17½, in the Centile app.
Get the Centile app
Free to download for iPhone and Android. Centile is for ages 13 and over.
Questions
Will my child end up inside this range?
Most children do, and a few finish outside it. It’s a guide, not a promise.
Does it use my child’s age or height?
No. It uses only each parent’s height, and boy or girl.
What if I’m worried about my child’s growth?
Talk to a doctor. This calculator can’t spot a growth problem, and it isn’t medical advice.