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Average Height for an 8 Year Old

The average 8 year old boy is 128 cm (4 ft 2 in) and the average girl is 127 cm (4 ft 2 in). Full percentile tables for both sexes, plus what to expect as your child grows.

calendar_today1 June 2026 schedule5 min read scienceBased on CDC data

Age 8 is squarely in the middle of childhood — boys and girls are nearly identical in height, and both are growing at a steady, predictable rate of around 5–6 cm per year. Puberty is still several years away for most children this age, which means height variation is relatively small compared to the teen years.

Quick answer: The average 8 year old boy is 128 cm (4 ft 2 in) and the average girl is 127 cm (4 ft 2 in). Both sexes are nearly identical at this age. The normal range (5th–95th percentile) spans from about 119 cm to 138 cm.

Height percentile table — 8 year old boys

PercentileHeight (cm)Height (ft/in)
5th119 cm3 ft 11 in
10th121 cm3 ft 12 in
25th124 cm4 ft 1 in
50th (avg)128 cm4 ft 2 in
75th132 cm4 ft 4 in
90th135 cm4 ft 5 in
95th138 cm4 ft 6 in

Height percentile table — 8 year old girls

PercentileHeight (cm)Height (ft/in)
5th119 cm3 ft 11 in
10th121 cm3 ft 12 in
25th124 cm4 ft 1 in
50th (avg)127 cm4 ft 2 in
75th131 cm4 ft 4 in
90th134 cm4 ft 5 in
95th136 cm4 ft 6 in

Source: CDC 2000 Growth Charts. Values rounded to nearest centimetre.

What's typical for an 8 year old's growth?

Children at age 8 are in a stable, predictable growth phase. Expect your child to grow approximately 5–6 cm per year between ages 6 and 10. Growth should be fairly consistent from year to year — a sudden slowdown (less than 4 cm/year) is worth noting.

Boys and girls are almost identical in height at age 8, with girls typically within 1 cm of boys. This near-equality begins to shift around age 9–10, when many girls start their earlier puberty growth spurt and temporarily pull ahead.

Tracking growth over time: A single measurement matters less than the trend. If your child has consistently been at the 20th percentile and remains there, they are growing normally. See the full height chart from age 4 to 16 to track your child's trajectory.

When to speak to a doctor

Most height variation at age 8 is normal. Consider a check-up if:

  • Your child is below the 3rd percentile (shorter than 97% of peers)
  • Growth has slowed to less than 4 cm per year
  • There has been a significant drop in percentile channel over 12–18 months
  • Your child shows signs of puberty — breast development or pubic hair — before age 8 (girls) or age 9 (boys), which may indicate precocious puberty

References

  1. Centers for Disease Control and Prevention. CDC Growth Charts: United States. 2000.
  2. Khamis HJ, Roche AF. Predicting adult stature without using skeletal age. Pediatrics. 1994;94(4 Pt 1):504–507.

Medical disclaimer: This article is for informational purposes only. Consult a paediatrician with any concerns about your child's growth.

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