What does height percentile mean?

A height percentile tells you what percentage of people of the same age and sex are shorter than you. For example, the 75th percentile means 75% of people in that reference group are shorter and 25% are taller. The 50th percentile is exactly median height. Percentiles above 85 are considered tall for age and sex; below 15 is considered short. Neither extreme is necessarily cause for concern without other clinical signs.

What growth charts are used in this calculator?

For children aged 2 to 17, this calculator uses mean and standard deviation values derived from the CDC 2000 growth reference charts, which are widely used by health professionals. For adults aged 18 and over, it uses approximate population reference values. The percentile is calculated by converting height to a z-score (z = (height - mean) / SD) and then converting the z-score to a percentile using the standard normal cumulative distribution function.

What height percentile is considered normal?

The 5th to 95th percentile range is generally considered within the normal range for height. A child below the 3rd or 5th percentile or above the 97th or 95th percentile may be referred for further assessment, particularly if this represents a change from their previous growth pattern. For adults, percentile is used for comparison rather than clinical diagnosis. If you are concerned about a child's growth, speak with a paediatrician or GP.

Height Percentile Calculator

This calculator works out what height percentile you or your child falls into compared with others of the same age and sex, showing whether a height sits in the typical range or towards the short or tall end. Select the sex, choose an age group (individual years from 2 to 17, or an adult band from 18 to 24 through to 65 and over), and enter height in centimetres or feet and inches. It returns your percentile, your z-score, the reference mean height for your age and sex, and your entered height, plotted on a 0th-to-100th percentile bar so you can see your position at a glance. A detailed breakdown adds the reference standard deviation and height values at the 5th, 10th, 25th, 50th, 75th, 90th and 95th percentiles, so you can compare against several benchmarks rather than one number alone. A short written result flags whether you fall below the 5th percentile (short stature), above the 95th (tall stature), or within the typical 15th-to-85th percentile range. Percentile is calculated from a z-score based on CDC 2000 growth reference data for children aged 2 to 17, and approximate adult population reference values for those 18 and over. This is a general indication only, based on population averages rather than a clinical assessment, so speak with a GP or paediatrician if you have concerns about a child's growth.

Calculate.co.nz is proud to be partnered with Premium Homes, a recognised leader in eco-friendly, sustainable, and energy-efficient homebuilding. With a dedicated team and award-winning experience, they create homes that prioritise health, comfort, and long-term performance. Their founders, Andrew and Kelly, set out to raise the standard of residential construction in New Zealand by combining practical building expertise with a clear commitment to doing things better for homeowners.

Reference data: CDC 2000 Based on CDC 2000 growth reference charts and NHANES population data for adults.

1. About You

Sex

Age group

2. Your Height

Height unit

Height (cm)

Feet

Inches

Your Height Percentile

Percentile
60th
vs same age and sex

Z-Score

0.25

Standard deviations from mean

Reference Mean

138.5 cm

Average height for age/sex

Your Height

140.0 cm

Entered height

Percentile Position

0th10th25th50th75th90th100th

Height Breakdown

SexMale

Age group10 years

Your height (cm)140.0 cm

Reference mean (cm)138.5 cm

Reference SD (cm)6.0 cm

Z-score0.250

Percentile60th

Percentile Reference Points

5th percentile128.6 cm

10th percentile130.8 cm

25th percentile134.5 cm

50th percentile (median)138.5 cm

75th percentile142.5 cm

90th percentile146.2 cm

95th percentile148.4 cm

Result: Enter your details above to see your height percentile.

How Height Percentile Is Calculated

A height percentile is calculated using a z-score, which measures how many standard deviations your height is above or below the reference population mean for your age and sex.

The formula is:

z = (your height - reference mean) / reference standard deviation

The z-score is then converted to a percentile using the standard normal cumulative distribution function (CDF). A z-score of 0 corresponds to the 50th percentile (median). A z-score of +1 corresponds to approximately the 84th percentile, and a z-score of -1 corresponds to approximately the 16th percentile.

Reference Data Used

For children and teenagers aged 2 to 17, this calculator uses mean (L50) and standard deviation values derived from the CDC 2000 growth reference charts, which are based on NHANES (National Health and Nutrition Examination Survey) data and are widely used by paediatricians and growth specialists.

For adults aged 18 and over, mean and standard deviation values are drawn from published NHANES adult body measurement data by age group.

Worked Example

A 10-year-old male with a height of 140 cm (the calculator defaults):

Reference mean for 10-year-old males: 138.5 cm
Reference standard deviation: 6.0 cm
Z-score: (140 - 138.5) / 6.0 = 0.25
Percentile: normCDF(0.25) = approximately the 60th percentile

This means a 10-year-old male at 140 cm is taller than approximately 60% of boys the same age.

Percentile Ranges and What They Mean

Percentile Range	Interpretation
Below 3rd percentile	Short stature; may warrant clinical review
3rd to 15th percentile	Below average; within broad normal range
15th to 85th percentile	Average range
85th to 97th percentile	Above average; within broad normal range
Above 97th percentile	Tall stature; may warrant clinical review

Percentile alone does not indicate a health problem. Growth trend over time and family history are more informative. If you are concerned about a child's growth, consult a GP or paediatrician.

Children vs Adults

For children, height percentile is tracked over time against growth charts to check that a child is growing consistently along their growth curve. A sudden drop in percentile (or a consistently low percentile with short parents) may indicate a growth issue worth investigating.

For adults, percentile comparison is informational. Adult height is largely fixed by the early 20s, and percentile simply describes where someone sits relative to their peer group in the reference population.

Limitations

The CDC 2000 growth reference is based on a US population sample and may not perfectly represent New Zealand or other populations. It is used here because it is the most widely adopted standardised reference for ages 2 to 17. Height distributions do vary across ethnicities and generations. This calculator provides a general indication only and is not a substitute for professional clinical assessment.

Related Calculators

Sources and method: CDC 2000 Growth Charts for the United States: Methods and Development (Kuczmarski et al., Vital and Health Statistics Series 11, No. 246, 2002). NHANES adult anthropometric reference data. Z-score to percentile conversion using the standard normal CDF.

This calculator provides a general indication based on population reference data. It is not a clinical diagnostic tool. If you have concerns about your own or a child's growth, consult a registered health professional.