Average Height for a 3-Year-Old Boy

The average (50th-percentile) height for a 3-year-old boy (36 months) is 96.1 cm (37.8 in), based on the WHO Child Growth Standards. Across the healthy range, most boys this age stand between 89.1 cm (35.1 in) and 103.1 cm (40.6 in). (height is measured standing from age 2)

What's typical at this age

Three-year-olds typically add around 7 cm a year. Height now says more about eventual adult height than infant length ever did, though genetics gets the final word. Between 3 and 3½ years, the median boy grows about 3.8 cm.

A percentile compares your boy to other boys the same age — the 50th is simply the middle. Being above or below it is usually completely normal; a child who has always tracked the 15th or 85th percentile is typically growing exactly as they should. What pediatricians watch for is a sudden change in the pattern, not the number itself.

Percentiles calculated from the WHO Child Growth Standards (2006). For information only — not medical advice. If you're concerned about your child's growth, speak to your pediatrician or health visitor. Full disclaimer.