Average Height for Kids and Teens by Age (Boys & Girls)
"Is my child the right height for their age?" is one of the most common questions parents ask, and the honest answer depends on a few things a single number can't capture. Here is the average height for kids and teens at every stage from age 2 to the end of the growth charts, how wide "normal" really is, why boys and girls swap places on the chart during the preteen years, and when a height pattern is worth raising with a doctor.
Quick Answer
"Average" height is the 50th percentile: half of U.S. children of the same age and sex are shorter, half are taller. On the CDC growth charts the median 10-year-old is about 4'6.5" to 4'6.75" (roughly 138 to 139 cm) for both sexes, the median 18-year-old boy is about 5'9.25" (176 cm), and the median 18-year-old girl is about 5'4.25" (163 cm).[1] But "normal" is much wider than the average. About 9 in 10 healthy children fall between the 5th and 95th percentiles, which at age 14 is a spread of more than 10 inches for boys. A child's growth pattern over time matters far more than where a single measurement lands.
Average Height by Age: Boys and Girls
The table below uses the CDC's stature-for-age growth charts for ages 2 to 20, the reference most U.S. pediatricians use. It shows the median (50th percentile) plus the 5th and 95th percentiles, the range that includes about 90 percent of healthy kids, at every second birthday. The CDC data behind these charts have been unchanged since their release in May 2000.[1][2]
| Age | Boys | Girls | ||||
|---|---|---|---|---|---|---|
| 5th | Median | 95th | 5th | Median | 95th | |
| 2 years | 2'8" | 2'10.25" (87 cm) | 3'0.5" | 2'7.25" | 2'9.5" (85 cm) | 3'0" |
| 4 years | 3'1.75" | 3'4.25" (102 cm) | 3'7" | 3'1" | 3'3.75" (101 cm) | 3'6.75" |
| 6 years | 3'6.25" | 3'9.5" (116 cm) | 4'0.75" | 3'6" | 3'9.25" (115 cm) | 4'0.75" |
| 8 years | 3'10.75" | 4'2.5" (128 cm) | 4'6.25" | 3'10.75" | 4'2.25" (128 cm) | 4'6.25" |
| 10 years | 4'2.5" | 4'6.75" (139 cm) | 4'11" | 4'2.25" | 4'6.5" (138 cm) | 4'11" |
| 12 years | 4'6" | 4'10.75" (149 cm) | 5'3.75" | 4'6.75" | 4'11.75" (152 cm) | 5'4.25" |
| 14 years | 4'11.25" | 5'4.5" (164 cm) | 5'9.75" | 4'11" | 5'3.25" (161 cm) | 5'7.5" |
| 16 years | 5'3.25" | 5'8.25" (173 cm) | 6'1" | 4'11.75" | 5'4" (163 cm) | 5'8.25" |
| 18 years | 5'4.75" | 5'9.25" (176 cm) | 6'2" | 5'0" | 5'4.25" (163 cm) | 5'8.5" |
| End of chart (just under 20) | 5'5" | 5'9.5" (177 cm) | 6'2.25" | 5'0" | 5'4.25" (163 cm) | 5'8.5" |
Values are computed from the CDC 2000 stature-for-age parameters at each birthday and rounded to the nearest quarter inch; centimeter conversions are approximate. These are reference values for U.S. children, not a target every child should hit. For children under 2, see our guide to average height and weight for babies and toddlers.
Want a number for a specific age or month? Enter it into our Growth Percentile Calculator or the Height and Weight Calculator by Age for a personalized result.
Why Girls Lead at 11 to 13 and Boys Catch Up
Look closely at the medians and you'll see the two charts cross. At 10 they are within a quarter inch of each other. Around ages 11 to 13, the median girl is actually taller than the median boy, by under an inch. From 14 on, boys pull ahead, by about 1.4 inches at 14, 4.3 inches at 16, and more than 5 inches by the end of the chart. The reason is puberty timing: girls typically start their growth spurt about two years before boys.[4]
Girls' growth speeds up first, so they briefly lead in the preteen years. The median curve flattens out roughly two years earlier than the boys' curve.
Boys start later but grow for longer and gain more during their spurt, which is why the typical adult height gap is about five inches.
This is why comparing a boy against girls in his class, or the other way around, is always misleading. For the biology behind it, see our guide to height growth during puberty.
How Much Kids Grow Each Year
Heights tell you where a child is; yearly growth tells you how fast they're moving. The CDC median curves show growth slowing through childhood, spiking at puberty, then tapering off. These are gains along the median curve, so an individual child's fastest year, when it arrives, is usually larger than these figures because the median averages out different timing.[3][4]
Our Peak Height Velocity Calculator can help estimate whether a teen's fastest growth year is still ahead or already behind.
How to Read These Numbers
For an exact comparison, the Height-for-Age Z-Score Calculator converts a measurement into the same standard-deviation score clinicians record.
▶ Watch: Growth Chart Basics in 3 Minutes
Watch on YouTube ↗A limit worth knowing: the CDC charts describe how a large sample of U.S. children grew, using national survey data collected up to the mid-1990s.[2] They are a reference, not a standard of how every child "should" grow, and a single national chart doesn't fit every family's genetic background equally well.
Why the Same Height Drops on the Chart
One of the most confusing things about growth charts: a child who simply stops growing for a while doesn't hold their percentile, they slide down it, because the reference keeps climbing. For example, a median 10-year-old boy (about 4'6.75") who doesn't grow at all for a year would sit near the 25th percentile at 11 and around the 8th by 12. The table shows what the same 5'0" measurement means at different ages.
| A child who measures exactly 5'0" at age… | Boy's percentile | Girl's percentile |
|---|---|---|
| 11 | About 89th | About 87th |
| 12 | About 66th | About 55th |
| 13 | About 31st | About 24th |
| 14 | About 8th | About 11th |
| 15 | About 2nd | About 7th |
Percentiles computed from the CDC 2000 stature-for-age parameters and rounded.
That's why late bloomers can appear to "fall behind" right before a growth spurt and why pediatricians look at the slope of the growth line rather than any single point.
When to Talk to a Doctor
A pediatrician can plot a child's full growth record, check growth speed, and, if needed, order a bone age X-ray. Our Child Height Prediction Calculator and Bone Age Calculator are educational tools, not a replacement for that evaluation.
FAQs
What is the average height of a 10-year-old?
Is my child short if they're below average?
Why are some girls taller than boys at age 12?
At what age do boys and girls stop growing?
Can I use a child's percentile to predict their adult height?
References
- [1] Centers for Disease Control and Prevention, National Center for Health Statistics. CDC Growth Charts Data Files: stature-for-age, 2 to 20 years, LMS parameters and smoothed percentiles. cdc.gov/growthcharts/cdc-data-files.htm
- [2] Kuczmarski RJ, Ogden CL, Guo SS, et al. 2000 CDC growth charts for the United States: methods and development. Vital and Health Statistics, Series 11. 2002;(246):1-190.
- [3] Flegal KM, Cole TJ. Construction of LMS parameters for the Centers for Disease Control and Prevention 2000 growth charts. National Health Statistics Reports. 2013;(63).
- [4] Abbassi V. Growth and normal puberty. Pediatrics. 1998;102(2 Pt 3):507-511.
