Height Percentile Calculator

How to read the result

• Percentile. The 72nd percentile means the height is greater than that of about 72 out of 100 people of the same age and sex in the reference group, and less than about 28. The 50th percentile is the median: half are taller, half shorter.
• z-score. How far the height is from the median, measured in standard deviations of the reference group. 0 is the median, −1.88 is the 3rd percentile and +1.88 the 97th.
• Under 2 years, the WHO reference uses length measured lying down. A standing height is usually slightly shorter, so a lying-down measurement gives the fairer comparison.
• Adults get an approximate percentile: the survey publishes heights at the 5th, 10th, 15th, 25th, 50th, 75th, 85th, 90th, 95th percentiles, and the calculator estimates between them. Below the 5th or above the 95th it says so rather than guessing a number.

What this means, and what it doesn’t

• A percentile is not a diagnosis. It says where one height sits in a reference group, not whether a child is healthy or growing well. Being on the 10th or the 90th percentile is not better or worse than being on the 50th.
• One measurement doesn’t show growth over time. Growth is followed through several measurements, taken some months apart on the same chart. A single result can’t show whether a child is keeping to their curve.
• Measurements at home vary. Being out by a centimetre can move a young child’s result by several percentiles. Shoes off, heels against the wall, and a flat object on the head help.
• When to talk to a doctor. If a child’s result is below the 3rd or above the 97th percentile, or their percentile changes a lot between measurements, it can be worth mentioning to a doctor or health visitor. They can measure accurately and look at growth over time and family heights.

Who the reference groups are

• WHO (birth to 2 years) is an international standard. It describes how healthy, breastfed children grew in good conditions in Brazil, Ghana, India, Norway, Oman and the USA, measured 1997–2003.
• CDC (2 to 19 years) is a US reference. It describes how US children did grow, from national surveys between 1963 and 1994.
• NHANES (adults) is a US reference. It describes US adults measured between 2015 and 2018.

Results for children elsewhere may differ from their national charts. India, for example, has its own growth charts for school-age children from the Indian Academy of Pediatrics, and many countries use national charts. If a doctor or clinic uses a national chart, follow that chart.

Methodology and sources

Which reference is used

• Under 24 months: WHO length-for-age. From 24 months to 19 years 11 months: CDC stature-for-age.
• Why the switch at 2 years. The CDC recommends the WHO standards for children under 2 and its own charts from 2. At the same age the measurement also changes, from length lying down to height standing, which reads slightly shorter. So the curves step down a little at 2 years; the growth chart shows this as a dashed line.
• Adults (20 and over): NHANES 2015–2018. Without an age the calculator uses all adults 20 and over; with an age it uses the matching 10-year group, because older adults are shorter on average. The result names the group used.

How the percentile is calculated

• Children: the LMS method used by both WHO and CDC. For each age and sex the tables give three numbers: L (skewness), M (median) and S (spread). The height X becomes a z-score with Z = ((X / M)L − 1) / (L × S), or Z = ln(X / M) / S when L is 0, and the percentile is the share of a normal distribution below Z.
• Age. Ages are whole completed months. WHO rows are one per month. CDC rows sit on half months, so a child of 27 completed months is read at 27.5 months, the row covering 27.0 to 27.99. Between rows, L, M and S are interpolated in a straight line.
• Adults. NHANES publishes percentiles, not LMS values. The calculator converts each published percentile to its z-score and interpolates in a straight line between the two either side of the height, so the result is approximate.
• Units and rounding. Any unit you enter is converted to centimetres first. Percentiles are shown as whole numbers from 1st to 99th (or “below the 1st” and “above the 99th”), and z-scores to two decimals.
• Checks. Our tests recalculate the published 3rd, 50th and 97th percentile heights for every row of both children’s tables. CDC values match to within 0.1 percentile. WHO publishes those heights rounded to 0.1 cm, so we check that L, M and S reproduce them to within 0.05 cm.

Sources

Data files: WHO boys (opens in new tab) and girls (opens in new tab) length-for-age percentile tables; CDC statage.csv (opens in new tab); NHANES Vital and Health Statistics Series 3, No. 46 (opens in new tab). Last checked 2026-10-02.

Where to go next

For adult averages around the world, see average height by country. To see a height next to other people, celebrities, animals or objects, open the height comparison tool.