Puberty begins at different ages for different young men, but usually starts between the ages of 9 and 14 and usually ends between ages 14 and 18.  As you can see, one boy may be finishing with puberty by age 14 while a classmate may only be starting puberty at 14.  This variation is largely genetic and the timing of puberty is often similar to that of other family members.  Puberty should not begin before age 9, but it should have started by age 15.  Click to learn about disorders that cause puberty to begin before age 9 or after age 14.  


Young boys often anticipate getting taller and having facial and body hair.  On the other hand; they may dread being gangly, having their voice crack, or getting acne.  Changes occur in the size and appearance of the genitals; as well as sexual functions, such as having erections and gaining the ability to ejaculate and have wet dreams. These changes occur in stages throughout puberty. 


There are five main stages of measuring puberty that are routinely accepted.  These are the Tanner Stages of puberty.[i] [ii]  The changes tracked are growth, physical appearance (physique), voice changes, skin changes, chest/nipple changes, facial and body hair, pubic hair, scrotum color and texture, testicle size, penis size, frequency of erections, and ability to ejaculate and have wet dreams.



  • Stage 1 is the onset of puberty.  Sometimes it is called “pre-puberty.”  It begins between ages 9-12 (average is 11).  Typically few, if any, visible signs of puberty are present so the young man still looks like a boy.  Although there are no physical changes that are noticeable at this stage of puberty, the hypothalamus begins producing hormones that stimulate the pituitary gland to produce gonadotropins.  These gonadotropins then stimulate the testicles to produce testosterone. 


  • Stage 2 is when physical changes actually start to occur.  It typically begins between ages 9-14 (average is 12½).  This is when the earliest physical signs of puberty begin to appear as the testicles increase in size and begin pumping out enough testosterone to produce visible changes such as the start of pubic hair growth and the beginning of acne. 


  • Stage 3 is when physical changes really get underway.  It begins between ages 11-16 (average is 13).  Perhaps the biggest sign of this stage is when wet dreams begin. 


  • Stage 4 is when “manhood” starts setting in.  Physical changes are perhaps at their peak during this stage, as testosterone levels are at their highest.  Boyish appearances give way to a more “manly” physique.  In addition, the highly awaited time to start shaving occurs.  This stage begins between ages 11-17 (average is 14).  


  • Stage 5 is considered the end of puberty or the beginning of adulthood.  It begins between ages 14-18 (average is 16).   By this stage genital growth has reached its maximum and abdominal and chest hair, as well as other body hair, continues to grow.

See the following chart for all the various changes that occur in each of the Tanner Stages:

Puberty Table.jpg

Physical Growth and Physique


Young boys often anticipate the “growing up” portion of puberty – whether that’s to become taller or put on some muscle and look more “manly.”  During stages 1 and 2 there are few changes.  Growth continues at about 2 inches (5cm) per year and the boy still looks like a “boy.”  Towards the end of stage 2 the young man begins to lean up just a little bit and lose that boy-like “chubbiness.”  Stage 3 is really when growth starts changing noticeably.  At this stage growth increases to about 3 inches (8cm) per year and he starts developing more of your typical “male physique.”  However, stage 4 is really when the “growth spurt” occurs and is the peak of growth.  During stage 4 a young man can grow anywhere from 4-5 inches (10-12cm) per year.  It’s also when the shoulders begin to broaden and he can start placing a fair amount of muscle on his frame.   It is during these times of extreme growth that many young men become clumsy as they try to catch up to constantly changing leg length.  But as growth slows and eventually stops, so does the awkward, clumsy state.  By stage 5, vertical growth stops as the young man has reached his full adult height.  However, he can still increase in muscle mass and continues to develop a more masculine build and look (especially when facial hair and other body hair add to the look of maturity).


Voice Changes


One of the least anticipated events in puberty is the changing of the voice.  Before puberty and in the early stages of puberty; the larynx, which contains the vocal cords, are relatively small.  The vocal cords within the larynx are also small and thin.  However; around stage 3 of puberty, the larynx begins to grow.  This growth can be both seen and heard.  As the larynx grows in size, it begins poking out of the neck – we call this the Adam’s Apple.  As the vocal cords are stretched in the larynx, it can cause the voice to crack and change pitch – oftentimes uncontrollably.  In stage 4 the voice cracking goes away and the voice begins to deepen as the vocal cords lengthen and thicken.  By stage 5 the adult voice depth is reached.



The skin changes that are often most associated with puberty deal with two types of skin glands – sebaceous (oil glands) and apocrine (sweat glands).  Oil secretion (called sebum) from the sebaceous glands begins fairly early in puberty, usually during stage 2.  Young men will notice that their face, back, and chest get oily more frequently which often leads to acne.  Not only does the skin get oily, but these glands found near hair follicles lead to oily hair.  This requires young men to shower and wash their hair more frequently.  Sebum (oil) secretions can not only clog pores, but they create a breeding ground for bacteria leading to acne.  Since oil secretions begin around stage 2, so does the beginning of acne. 


Apocrine glands are found at the base of some body hair follicles (like armpit hair) and secrete proteins.  Bacteria growing on nearby sebum can cause these proteins to break down leading to body odor.  Since these glands develop earlier in puberty, it’s not uncommon for many young men to use deodorant or antiperspirant sooner rather than later. 

Since skin glands are stimulated by testosterone, acne and body odor tend to peak during stage 4 when testosterone levels are at their highest.  Although acne and body odor diminish as testosterone diminishes during stage 5, adult levels of hormones require good hygiene throughout life (click HERE to learn more).




We don’t often think of chest changes during puberty in boys, but there are definitely changes that occur in the chest.  These are often mild and passing.  The nipples tend to change color and texture and darken during stage 2.  As puberty continues they can swell and become tender.  This pain usually goes away by stage 5.


Testicular Size


Some medical providers may use orchidometers (small beads) that measure the size of the testicles to get a rough idea of puberty development.  Below are the approximate size changes in the testicles during puberty.  Due to differences in screen sizes common coins are shown next to testicular sizes (British, Canadian, and U.S. pennies as well as a 2 euro cent are all 19-20mm in diameter and are used as a frame of reference for testicular sizes below).

Testicular size.jpg

Note – testicular sizes using an orchidometer are for reference only.  Measuring testicular size is unnecessary during puberty and is often only performed if other signs of puberty are not occurring as expected.


Genital Growth

As a visual guide to the male genitals during the Tanner Stages, the following is a good summary that can be followed using the illustration to the right. 

  • Stage 1 – the genitals are the same as they were in childhood. 

  • Stage 2 – the testicles begin to grow in size and the scrotum begins to darken and change texture. 

  • Stage 3 – the penis grows in length, but it doesn’t grow much in width so it appears more “long and skinny.”  The testicles continue to grow and the scrotum continues to thin and darken. 

  • Stage 4 – the penis grows more and becomes wider.  This is also when the glans (tip) develops a darker, more adult-like appearance.  The testicles and scrotum continue to grow. 

  • Stage 5 – all of the genitals have reached their adult size and appearance.


The majority of genital growth occurs during puberty.  The testicles, scrotum, and penis all grow in size over the course of a few years.  Because of this rapid growth, it is possible for some young men to develop genital abnormalities.  The abnormalities may not have been noticeable to their parents when they were young but they definitely become apparent to young men in late adolescence and after puberty.  Although very rare, one such condition that can occur is a curvature of the erect penis caused by unequal growth of the erectile columns inside the penis (click HERE to learn more).


Pubic Hair

  • Stage 1 – there is little to no pubic hair (just fine "peach fuzz”). 

  • Stage 2 – darker, longer, fine hair typically starts growing right at the base of the penis, typically at the 10 o’clock and 2 o’clock positions. 

  • Stage 3 – the pubic hair spreads to cover the area above the penis.  At this stage it usually starts becoming courser and begins to curl. 

  • Stage 4 – pubic hair spreads outward toward the crease of the leg then downward toward the scrotum and eventually growing on the scrotum.  Pubic hair has adult appearance and coarseness; however, it hasn’t spread to its maximum extent.

  • Stage 5 – pubic hair spreads in all directions – behind the scrotum and up into the crack of the buttocks, upward toward the lower abdomen (usually including a small line of hair up to the belly button), sideways across the crease of the leg, and downward onto the legs/thighs.  In fact, pubic hair spreading onto the thighs is one of the final signs that puberty is nearing its end.

Caucasian skin tone was used with brown pubic hair and a circumcised penis in order to highlight the changes in scrotum and penile color, as well as the spread of pubic hair.  Similar changes are seen in men with darker skin tones and different colors of pubic hair.





Pubic hair is almost always the first body hair to begin growing during puberty (at stage 2).  This is followed later by the growth of facial and armpit hair, both at around stage 4 of puberty.  Eventually abdominal hair, then chest hair, often grows around stage 5.  The timing of body hair growth can vary from one young man to the next, as can the extent of where and how thickly body hair grows in certain areas.  Body hair can continue to spread after puberty during adulthood.


Facial hair typically begins to grow long after pubic hair has started growing (about stage 4).  Facial hair first appears at the sideburns and mustache area before filling in by spreading onto the cheeks, chin, jawline, and neck.  Facial hair can continue to thicken and spread after puberty during early adulthood.


Armpit hair typically appears a bit later than pubic hair.  A separate staging method of armpit hair has been recognized and is called the Wolfsdorf Staging for armpit hair.  It includes the following:

  • Stage 1 – no armpit hair growth

    • Often coincides with Tanner stages 1-3

  • Stage 2 – fine or scant hair growth

    • Often coincides with Tanner stage 3-4

  • Stage 3 – course hair but less than full adult growth

    • Often coincides with Tanner stage 4

  • Stage 4 – course hair that extends to full adult growth

    • Often coincides with Tanner stage 5

Pubic Hair Stages.jpg
Armpit Hair.jpg

Abdominal hair typically begins at the end of stage 5.  Usually a small line of hair begins growing from the pubic area up to the belly button in a narrow strip.  Abdominal hair may stop here or progress upwards above the belly button and outwards away from the belly button. 


Chest hair is often one of the last body hair areas to begin growth.  This can occur during stage 5, but for some men it may not occur until adulthood and continue increasing during adulthood. 


For more information on male body hair, click to learn more about facial, chest, abdominal, pubic/genital, buttocks, back, armpit, arm, hand/finger, leg, and foot/toe hair.




Erections increase in frequency during puberty, and at the height of puberty erections may become spontaneous and hard to control.  However; by the end of puberty, as testosterone levels drop, erections tend to be easier for a young man to control.

Ejaculation is often considered the “welcoming event” to sexual development.  Wet dreams (nocturnal emissions) occur when semen is ejaculated during sleep.  In boys who are not masturbating, the first wet dream typically occurs in Tanner Stage 3.  Semen is beginning to be produced in stage 2, so masturbation is possible before wet dreams start naturally during stage 3. Innocent exploration, hearing about masturbation from friends, or viewing pornography may lead to masturbation before wet dreams can occur.  In fact, one survey found that only about one-third of boys will first ejaculate by having a wet dream, while the other two-thirds ejaculate first by masturbation or some other form of sexual activity.  Since masturbation decreases the chance of having a wet dream, some boys may not experience a wet dream until long after stage 3; sometimes not until adulthood.  Below are results from a survey on first ejaculation during puberty obtained for this book:

Purbery Ejaculation Chart.jpg

Talking Openly About Puberty & Sexual Matters


It’s important for young men to feel they have an adult they can go to and talk about the changes that are occurring in their bodies.It is natural to be curious about these changes, and the information they get from peers is typically incorrect or exaggerated.


Changes in height, weight, muscle mass, and body hair can all be things many young men worry about – especially boys who are late bloomers.  However, some early bloomers feel self-conscious if it seems they are the only one in their class with body hair.  They may be significantly taller and bigger than their friends and feel out of place.  It’s also important to give early bloomers, late bloomers, and all boys in between, reassurance as they navigate the changes occurring in their bodies.


It’s also important to have a trusted adult that boys can discuss sexual matters with as they go through puberty.The male brain becomes sexualized during this time and greater interest in the opposite sex surfaces.Their bodies also begin changing as they experience erections, sexual arousal, and orgasm; either through wet dreams or masturbation.  Changing emotions and sensations also create a lot of curiosity.  This curiosity unfortunately leads, more often than not, to pornography as a means of “getting information” or as a means of “experiencing sexuality” on some level.  Masturbation also is an avenue to experiencing sexuality during these years.  It is for these reasons parents and guardians should talk openly and honestly about sexuality, pornography, masturbation, wet dreams, orgasm, girls, and any other topic no matter how sexual in nature, in order to help young men form healthy habits and correct viewpoints about sexuality.


Because pornography and masturbation are so common throughout puberty it is important to have open and honest conversations about pornography and masturbation – the earlier the better.  Typically the first exposure to pornography is around age 8 or 9…coinciding with stage 1 puberty for some boys.  An entire section dedicated to pornography and masturbation addiction (to learn more, click HERE).  Since wet dreams become a part of life a specific section on wet dreams is dedicated to helping not only young men, but adult men make sense of why wet dreams happen (or don’t happen). Specific questions about wet dreams can be found by clicking HERE.

With few exceptions, nearly all male reproductive disorders can happen to young men going through puberty or just finishing puberty.Since their bodies are changing so rapidly, young men may often mistake the symptom of a disorder as just another change their body is going through.Young men are often undertreated for conditions ranging from prostatitis to jock itch.In fact, some diseases are more common during puberty than they are during adulthood (testicular torsion and testicular cancer being two of them).Other disorders may not become apparent until sexual maturation sets in (such as wet dream difficulties or penile curvatures).In addition, sexual experimentation (including masturbation) can lead to mental disorders such as addiction, depression, and anxiety disorders.They can also lead to some reproductive disorders such as prostatic congestion and pelvic tension disorder.

[i] - 10-5-16

[ii] - 10-5-16

Images on this page from top to bottom include:

  1. Original Table Design

  2. Claudio Divizia/ &Pykodelbi/

  3. Original Design

  4. Original Design

  5. Original Table Design