Child Height Percentile by Age and Sex

A height percentile answers a comparison question: where does one recorded height sit in the WHO 2007 height-for-age reference for the same age and sex? It does not grade the person, and it does not say how tall they will be as an adult.

The height percentile page explains that comparison. The height calculator applies it to a height, age, and sex you enter. The growth charts show the curves the number comes from.

What the percentile means

If a recorded height is at the 40th percentile, about 40 out of 100 children and adolescents of the same age and sex in the WHO reference are shorter, and about 60 are taller. The number describes the reference. It is not a mark out of 100.

The 50th percentile is the median. In the reference, about half are shorter and about half are taller. It is a middle value, not a target, a prize, or the height someone is supposed to reach.

A 25th percentile means about 25 out of 100 in the reference are shorter. A 75th percentile means about 75 out of 100 are shorter. Both are ordinary places on the curve. A lower percentile is not automatically a problem, and a higher percentile is not automatically healthier.

How the comparison is calculated

The reference used here covers ages 5–19. Age is completed calendar months from the date of birth to the measurement date. The measurement month counts only once its day reaches the birthday day. That completed month selects one published row, from 61 through 228 months. The comparison does not interpolate between rows. Months before 61 and after 228 are outside this reference, so this method does not produce a percentile there.

The percentile comes from how far the recorded height sits from the median of that one row. Growth science describes the z-score form of the same comparison. The result is a statement about today’s height in the reference. It is not a future height.

Why age and sex matter

WHO publishes separate height-for-age tables for boys and girls, and the typical height in the reference changes with age. The same height in centimeters can sit in a different place for boys than for girls, and in a different place a year later, because each comparison uses its own row. A height percentile by age only makes sense on the table it was calculated from.

That is why the calculator asks for both age and sex. Without them, the comparison is not the WHO height-for-age comparison.

Does one measurement tell the whole story?

A single height is useful, and it is limited. Posture, the time of day, and small differences in technique can change a reading. One unusual result is a reason to measure again with the same method, not a reason to rewrite the whole story.

How should changes over time be read?

A series of measurements shows whether a child or teenager is tracking along a similar part of the reference or moving relative to it. That pattern is more informative than any one percentile. How to read a growth chart walks through one point on those curves. The change from one recorded height to the next is growth velocity, which answers a different question from the percentile.

Common questions

Is a higher percentile healthier?

No. A higher place in the reference is not a health grade, and a lower place is not automatically a problem. The percentile only says where one recorded height sits in the spread.

Should a child be near the 50th percentile?

No. The 50th percentile is the median of the reference, not a goal.

Does this percentile predict adult height?

No. Later measurements, the timing of puberty, and family background sit outside a single percentile. Growth Predictor does not turn today’s percentile into a future height.