Average Penis Size: Reference Ranges & 9 FAQs

Updated in February 2023

The average size of an erect penis can vary from about 4 to 6 inches (10 to 16 cm), although this average tends to fluctuate depending on men’s racial backgrounds, as certain races seem to have higher or lower averages. However, only 3% of men measure outside of this range.  

The period of most growth occurs during adolescence, after which penis length and width remains the same. 

A penis that is significantly below the average penis size is referred to as a micropenis. It is characterized by a penis that measures less than 5 cm (roughly 2 inches). 

Imagem ilustrativa número 1

1. What is the average penis size?

The average size of a flaccid penis seems to be around 9 cm (3.5 inches), while an erect penis is around 13 cm (5.1 inches). Average circumference varies between 9 and 12 cm ( 3.5 to 4.7 inches). 

Penis size can vary greatly from man to man, and is related to various factors such as hormone production.

2. At what age does a penis stop growing?

In most boys, penis growth will halt at around 20 years of age. After this age, size remains relatively the same. 

Although penis growth occurs during adolescence, the rate of growth can vary from boy to boy, and can be faster in some than in others. By about 19 years of age, the penis should have developed almost completely. 

3. Is is possible to enlarge your penis? 

There are many techniques that can be used to increase penis size, although many of these are not scientifically supported as safe. Small are only able to achieve minimal results. Read more about penis enlargement techniques and whether they really work.

4. How do I measure a penis?

Sensitive content
This file may contain unpleasant images that are not suitable for all audiences.
Imagem ilustrativa número 2
Como medir o pênis corretamente

Penis size should be measured when the penis is erect. You should measure the distance between the suprapubic region (the bone directly above the base of the penis) and the penis tip. 

Some men will carry more fat around the suprapubic area which can cover some of the penis. In these cases, measurements may not be accurate, and should therefore be taken while lying down. 

5. Does size matter?

In many studies done on penis size, it was concluded that men are more worried about their own penis size. There is little worry or dissatisfaction reported from the sexual partner. 

Furthermore, in most cases, penis size do not interfere with sex or fertility. 

6. Can smoking reduce penis size? 

Smoking does not directly interfere with hormone production, and therefore does not reduce penis size. However, because smoking negatively affects other organs in the body, over time it can interfere with penis functioning, specifically erections. Erectile dysfunction can occur because prolonged cigarette use can block blood vessels, which can reduce blood flow to the penis. This can affect a man’s ability to produce and maintain an erection.

7. Can a penis grow crookedly?

It is common to note a penis growing with a slight tilt to one side or the other. This mainly occurs because the urethra development does not always accompany penis development, which gives the penia a slight curve. 

As long as the curve is not associated with pain and does not interfere with penetration, it is not a clinical concern. 

8. What doctor should I consult about penis size? 

Doctors who specialize in male genital problems are referred to as urologists. These doctors can help with any doubts about penis size and other genital issues. They are most qualified to assess your concerns, like whether penis enlargement surgery is right for you. 

9. Can masturbation interfere with penis growth?

Masturbation does not interfere with penis growth, as size is wholly determined by genetics. Therefore sexual acts will not lead to or diminish growth.