At present, there is no accurate medical conclusion about the age at which boys stop growing taller. Most boys are developing before 18 years old, and their height will continue to grow. Boys reach puberty at the age of 12~ 14, which is the second peak of height growth. Before puberty, the height growth rate is relatively fast, at least 7~8 cm long a year, even reaching 10 cm or more. In the late adolescence, the development of sexual organs gradually matures, and the growth rate of height will also slow down. 18 years old, the secondary sexual characteristics appear completely, the Adam's apple grows, the testis and scrotum mature, and the voice changes. At this time, the height basically stopped growing.
The criterion for judging whether the height stops growing is not age, but bone age. It is necessary to test the bone age to determine whether the epiphyseal line is closed. As long as the epiphyseal line is not closed, it will continue to grow no matter how old you are. Most boys will close their epiphyses and stop growing in height when they are around 18 years old. However, some boys develop late, and the epiphyseal line over 18 years old is still not completely closed. At this time, their height will continue to grow, and may stop growing after 19 or 20 years old.