For boys, an androgen called testosterone is the principal sex hormone.
While testosterone is produced, all boys' changes are characterized as virilization, a substantial product of testosterone metabolism in males is estradiol.
The conversion of testosterone to estradiol depends on the amount of body fat and estradiol levels in boys are typically much lower than in girls.
Although boys are on average 2 centimetres (0.8 in) shorter than girls before puberty begins, adult men are on average about 13 centimetres (5.1 in) taller than women.
Most of this sex difference in adult heights is attributable to a later onset of the growth spurt and a slower progression to completion, a direct result of the later rise and lower adult male levels of estradiol.
On average, girls begin puberty around ages 10–11 and end puberty around 15–17; boys begin around ages 11–12 and end around 16–17.
Puberty which starts earlier than usual is known as precocious puberty.
The first androgenic hair resulting from adrenarche can be also transient and disappear before the onset of true puberty.