Is my penis normal?

10th May, 2019 • 4 min read

It’s not unusual for a man to worry about the size of his penis, or to want to know if their penis is normal. An online survey of more than 50,000 people revealed that 45% of men would like a larger penis.

But what is ‘normal’? There really is no such thing, as every individual is different. It is only important that you know what is normal for you so you can detect when something is wrong. For example, if you have a

sexually transmitted infection

However, studies have found some averages about penises which you can read more about below.

Average penis size

The average length of a man’s penis when not erect is around 9cm (3.75in). When erect, the average length is around 13-18cm (5-7in).

However, it’s completely normal for your penis to be longer or shorter than this. There are also things which can temporarily affect the size of your penis, such as swimming or being cold.

As well as size, there is variation in the angle of an erect penis. There is no right shape or angle, but if there is a significant bend in your penis (which may cause you pain or difficulty having sex) you should see a doctor as this may be a symptom of Peyronie’s disease.

When to worry about your penis

Signs of an STI

If you are concerned you may have been exposed to an STI you should get tested as soon as possible.

Some STI symptoms which affect the penis include:

  • Unusual discharge from the penis
  • Pain when peeing
  • Lumps or skin growths around the genitals or anus
  • A rash
  • Itchy genitals or anus
  • Blisters and sores around the genitals or anus
  • Irritation of the urethra (the tube urine comes out of)

Erectile dysfunction

Erectile dysfunction is when you are unable to get or maintain an erection. There are different causes of erectile dysfunction, including anxiety, hormonal problems, injury, or high blood pressure.

It's important to see your doctor if you are experiencing erectile dysfunction so they can determine the cause.

If you know what is causing your erectile dysfunction then you can get the right treatment, and reverse the symptoms.

Learn more about erectile dysfunction

Painful erections

Priapism is an ongoing and often painful erection which can last for many hours. It is a medical emergency, so you should seek immediate medical attention if you think you have it.

Symptoms include:

  • An erection unrelated to sexual stimulation
  • An erection which does not go away after ejacualtion
  • An erection which lasts longer than four hours
  • The shaft of the penis is rigid but the head is soft

If priapism isn’t treated in the first 24 hours it may cause permanent damage to your penis, so it’s important to seek help as soon as possible.


Balantis is the swelling of the head of the penis. It can also affect the foreskin.

Symptoms include:

  • A sore, itchy and smelly penis
  • Redness and swelling
  • A build-up of thick fluid
  • Pain when peeing

If you are experiencing these symptoms you should see your doctor to rule out anything more serious.

Learn more about balanitis

Penile cancer

Penile cancer is a very rare form of cancer which occurs on the skin of the penis or within the penis. It most commonly affects men over the age of 50.

Its symptoms include:

  • A sore or lump on the penis
  • A change of skin colour in the affected area
  • Thickening of the foreskin or skin of the penis
  • A rash

If you have any of these symptoms, you should see a doctor. It is unlikely they will be caused by penile cancer (in the UK, fewer than 550 new cases are diagnosed each year) but it is best to check.

Learn more about penile cancer


Phimosis, or tight foreskin, is not uncommon in babies and children, but is less common as you get older.

If older children or adults experience tight foreskin then they should see a doctor because it can be due to a skin condition and can cause scarring.

If you are having difficulty urinating you should seek immediate medical help.

Find out more about phimosis


There’s no such thing as a ‘normal’ penis, everyone’s penis is different and will vary in size and shape. The most important thing is to know your normal, and to see a doctor if you experience any of the symptoms described above, or you are worried about your penis.

Quick Quiz

The average penis is around 13cm in length when not erect. True or false?

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.