Growth Chart

The chart is height for age: age along the bottom in years, height up the side in centimetres, and 7 curves, one for each of the 3, 10, 25, 50, 75, 90, 97th percentiles of the chosen reference. Every curve is computed from the published L, M and S values at each month of age, so the picture is the reference itself rather than a tracing of a printed chart. The median curve is drawn heavier, each curve is named at its right-hand end, and moving over the chart reads the 3rd, 50th and 97th percentiles at any age.

On the WHO reference the median girl grows from 109.4 cm at 5 years to 161.7 cm at 15; on the CDC charts the median boy goes from 50 cm at birth to 176.8 cm at 20. Those figures are read straight from the tables, and the table under the chart lists the 3rd, 50th and 97th percentiles at every birthday for the reference and sex in view.

A point on the 75th curve means a child taller than about 75 in 100 children of the same age and sex in the reference population. The band between the 3rd and 97th curves holds 94 in 100 of them, which is why those two are the outer lines on most printed charts. The curves rise steeply in infancy, flatten through childhood, rise again around puberty and level off in the late teens; the timing of that last rise differs between boys and girls, so the chart always shows one sex at a time.

Both references switch from lying-down length to standing height at 2 years, and standing height is a little less than length, so the curves have a small step at 24 months. The chart keeps it because the references do. Percentiles describe a population, not a target: healthy children are found on every curve.

WHO draws the WHO Child Growth Standards (birth to 5 years) followed by the WHO 2007 Growth Reference (5 to 19 years), the international set. CDC draws the 2000 CDC growth charts, the set used in the United States, from birth to 20 years. They differ a little in the median and the spread at a given age because they come from different populations and methods, so the same measurement can sit on a slightly different curve on each. The chart, the plotted point and the table all follow whichever reference is selected, and the reference is named on every one of them.

Enter a child's sex, age in years and months, and height, and the measurement appears as a dot on the curves with its percentile and z-score beside the chart. Plot each past measurement in turn to see how a child has tracked; the height percentile calculator gives the same numbers with more room for the result. Nothing you enter leaves your browser, and a shared link carries only the sex, reference, age and height.

A dot on the chart is a snapshot, not an assessment. Clinicians read growth from a series of measurements over time and from everything else they know about the child; this page draws published curves and plots a point, and does not interpret where it falls.

• CDC National Center for Health Statistics, 2000 CDC Growth Charts: percentile data files with LMS values — statage.csv (stature-for-age, 2 to 20 years) and lenageinf.csv (length-for-age, birth to 36 months): L, M and S by sex and age in months. Checked 2026-09-20.
• WHO Child Growth Standards: length/height-for-age, birth to 5 years (z-score tables) — Monthly L, M and S for boys and girls: recumbent length to 24 months, standing height from 24 to 60 months. Checked 2026-09-20.
• WHO Growth Reference 2007: height-for-age, 5 to 19 years (z-score expanded tables) — Monthly L, M and S for boys and girls from 61 to 228 months. Checked 2026-09-20.