Boys typically stop growing in height around the age of 16, with most completing their growth by 18 years old when puberty finishes and growth plates close. However, some boys may continue to grow slightly into their early 20s, though this is rare and usually involves only a small increase in height
. Puberty, which usually starts between ages 8 and 14 (commonly around 12), triggers a growth spurt that lasts 2 to 5 years. Boys grow fastest about 1 to 2 years after puberty begins and generally reach about 92% of their adult height during this period
. The timing of puberty affects when growth starts and stops but not the final height. Muscle development continues into adulthood, often peaking in the 20s and 30s, even after height growth has ceased
. In summary:
- Most boys stop growing in height by 16 to 18 years old.
- Growth plates close around 18, ending height increase.
- Rarely, some may grow slightly into their early 20s.
- Muscle growth continues beyond height growth.
This variation depends on genetics, nutrition, and overall health
