How tall will I be?
A free height calculator built on the CDC growth charts — the same adult height predictor inside the MaxHeight app. Enter your age, height and your parents’ heights to see the range your future height will most likely land in. The app shows the number inside that range and narrows it as you log your height. No account, and nothing is stored.
Your likely adult height
Pick a sex, age and height and the range your adult height will most likely land in appears here instantly.
Log your height weekly and the prediction keeps sharpening — free to download on the App Store.
The app shows the number inside your range, and your own measured growth tightens it as you track.
How this height calculator works
It blends up to three estimates a pediatrician would recognise. The genetic target is the Tanner mid-parental formula — your parents' average height, plus 2.5 inches for a boy or minus 2.5 inches for a girl — pulled part of the way toward the population average, because children of very tall or very short parents usually land closer to the middle. The growth trajectory divides your current height by the share of adult height a typical child of your age and sex has already reached, from the CDC medians, adjusted for puberty stage. If you know how much you grew last year, a growth-rate estimate projects that pace over the growing years typically left. The estimates are averaged and kept inside what remaining growth could physically produce. It's the same code that runs inside the MaxHeight app.
How accurate is a height calculator?
Honest ones give a range, not a number. Parents' heights alone leave a spread of a few inches in either direction; adding your current height, age, puberty stage and growth rate narrows it, which is why this calculator leads with the range. The app shows the number inside it and keeps narrowing the range as you log your height. A bone-age X-ray read by a doctor is more precise than any formula.
Can I predict my height from my parents' heights?
Roughly, yes. Average your parents' heights, then add 2.5 inches for a boy or subtract 2.5 inches for a girl. That is the mid-parental formula, and it is the first thing a pediatrician checks. It gives a target with several inches of range around it, so this calculator also uses your own height and age to see how you're tracking toward it.
At what age do boys and girls stop growing?
Most girls finish between 14 and 16, about two years after their first period. Most boys finish between 16 and 18. Puberty timing shifts both windows by a year or two in either direction, which is why the puberty question matters more than it looks.
How tall will my child be?
Enter your child's sex, age and height, plus both parents' heights. From about age 2, children tend to track along a percentile line on the CDC growth charts, so their current percentile plus the genetic target gives a useful early estimate. Expect a wider range for young children, because their puberty timing is still unknown.
Sources: CDC growth charts · CDC stature-for-age LMS data · Tanner et al. (1970) · NHANES adult reference. Not affiliated with any of them. Curious how you compare today? Average height by age.