During puberty, the penis will grow in both length and girth. Once puberty ends, there is unlikely to be any further penile growth. However, some individuals may experience penis growth into their early 20s.

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Many people have concerns about the size of their penis at some point. However, research shows that most have a penis size within typical ranges.

Studies also indicate that most people are happy with the length of their partner’s penis.

In this article, learn about penile growth during puberty, the average penis size, and the truth behind some of the most common penis size myths.

A note about sex and gender

Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Click here to learn more.

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For males, puberty occurs on average between the ages of 9 and 14 and usually lasts for 3–4 years.

During this time, the penis will get longer and thicker. The rate at which growth occurs varies from one person to another.

Other changes that affect the penis and genitals during puberty include:

  • testicle growth
  • thinning and reddening of the scrotum
  • pubic hair growth around the penis
  • nocturnal emissions of semen, or “wet dreams
  • more frequent erections and ejaculation

Research on 15,521 men worldwide reported that the average penis length is 3.61 inches (in) or 9.16 centimeters (cm) when flaccid and 5.16 in (13.12 cm) when erect.

Additionally, the average girth, or circumference, is 3.67 in (9.31 cm) when flaccid and 4.59 in (11.66 cm) when erect.

Studies show that most males who believe they have a short penis overestimate the average penis length. Many people commonly estimate the length of their penis to be at least 6 in. However, in a review of 21 studies in which researchers had measured the penis when erect, researchers found the average length to be 5.1 to 5.5 in.

A few different factors may play a role in determining the size of a person’s penis. Genetics may predispose someone to a particular penis size. The level of testosterone in the body can also influence it.

Additionally, research indicates that exposure to certain chemicals in the womb may affect how genes and hormones manifest in the body, which can also affect penis size.

Similarly, not getting adequate nutrition in the womb can influence penile development.

In adulthood, having excess weight can make the penis look smaller, as can having a lot of public hair.

Learn more about factors that may affect penis size.

There are many products — including devices, pills, and creams — that claim to increase penis length and girth. The internet also holds many claims that stretching exercises may have similar effects.

However, according to the Urology Care Foundation, almost none are effective. That said, there is some limited scientific research to suggest that penile extenders may increase length but not girth.

For observable results, it may be necessary to use these devices for several hours per day over 3–6 months. Note that the studies showing benefits face criticism in terms of small sample size and selection bias.

Instead of using unproven devices and techniques, some people may benefit from improving their self-esteem and body confidence by seeking counseling and exercising as much as possible.

However, there are also a few tricks that individuals can try to make the penis appear bigger. These include maintaining a moderate weight and trimming back pubic hair.

There are a number of myths about penis size and shape, and these can cause unnecessary stress and feelings of inadequacy in people of all ages. The following are among the most common myths:

1. Shoe size correlates to penis size

There is a common belief that a male’s foot or hand size indicates the size of their penis. This is simply untrue. There is no link between the size of the penis and that of another body part.

2. The size of a flaccid penis indicates its size when erect

There is no link between the size of a penis when flaccid and erect. The length of a flaccid penis varies greatly from person to person, and many factors can influence it, including room temperature.

3. Most people want their partner’s penis to be bigger

Many people seem to believe that their partner would like it if their penis were larger. However, research seems to indicate that this is not the case.

One older study from 2006, for example, reports that only 55% of men were happy with their penis size, while 85% of women expressed satisfaction with the size of their partner’s penis. No newer data appears to be available. More research is necessary to understand the current preferences of partners.

4. A longer penis increases sexual satisfaction

Another concern for some males is that a longer penis increases sexual pleasure for one or both partners. However, one study from 2015 suggests that at least some females rate girth as more important than length for satisfaction.

It is also important to note that several other factors play a role in sexual satisfaction, including individual-, partner-, and relationship-related factors.

For example, research indicates that the level of arousal and previous ejaculation can also play a role. Certain factors, such as the degree of communication with one’s partner and personal life circumstances, can also play a role in sexual satisfaction. This means that sexual satisfaction is multifaceted and cannot be entirely dependent on penile size.

A micropenis is a very small but typically structured penis. It results from either hormonal or genetic abnormalities.

Doctors usually diagnose this rare condition when the penis measures 2.5 standard deviations below the average stretched length.

Although there is no cure, hormone therapy may stimulate growth in children with a micropenis. Surgery is another option, and early diagnosis and treatment tend to provide the best outlook.

It is important to remember that micropenis is very rare, occurring in 1.5 per 10,000 male newborns in North America.

Learn more about micropenis.

People who have concerns about the appearance of their penis or how it works can speak with a doctor.

A doctor can provide support and reassurance about penis size and shape. They can also investigate any health issues that may be affecting the size or appearance of the penis, provide a diagnosis, and put together a treatment plan.

For example, a person can have a disorder that causes the penis to bend or curve, such as Peyronie disease.

Parents and caregivers who suspect their child has a micropenis should consult a doctor. Early treatment often provides the best outcome.

The following are common answers to questions about penile growth:

How many inches can a penis grow?

In rare cases, a person’s penis can grow much larger. According to an article, at least one person reportedly has a 13.5-in penis. However, this is not a typical size. The average penis length is 5.1 to 5.5 in.

How long does the penis keep growing?

Once puberty ends, the penis will stop growing. This typically occurs when a person reaches around 18 years of age.

Does circumcision affect penis size?

Circumcision should not affect penis size if the practitioner performs the procedure correctly. There are only a few studies indicating a possible relationship between circumcision and lower penis length. However, the researchers may have looked at a population where circumcision is not common and did not clearly account for all controls. Alternatively, they may have used a small sample size.

Many people worry about the appearance of their penis at some point in their lives. Common myths often fuel these concerns. Knowing the facts about average penis size can help individuals become more confident about their bodies.

As research seems to suggest, most males overestimate the average penis size. Studies also indicate that most females are happy with the size of their partner’s penis.

Those with persistent concerns about their penis size may benefit from seeing a doctor or mental health professional for support and guidance.