How do you measure up? Study determines average manhood size worldwide

Is your penis normal?

For everyone who has ever wondered, UK researchers have found an answer to average penis size after analysing 20 studies of more than 15,500 men of all ages and races.

Men are often left confused and concerned about whether they're small or normal, either flaccid or erect, the study in BJUI International says.

"Many men may present to urologist or sexual medicine clinics with a concern about their penis size, falling within a normal range," says the paper led by The Institute of Psychiatry, Psychology and Neuroscience at King's College in London.

Some men are severely distressed with the size of their penis and may be suffering from body dysmorphic disorder - the condition of believing their appearance is defective and needs to be fixed in some way, they says.

The answer is the average length of a flaccid penis is 9.16 centimetres or 13.24cm when stretched.

For an erect penis it is 13.12cm.

The average circumference of a flaccid penis is 9.31cm, or 11.66 cm when erect.

The authors say they hope their charts will be useful in clinical and therapeutic settings to counsel men, and for academic research.