New Study Gives ‘Definitive’ Answer on Average Penis Size

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News Sexual Health

New Study Gives ‘Definitive’ Answer on Average Penis Size

Martha Kempner

Results from more than 15,000 men show that the average penis is about five inches when erect.

Men are worried about their penis size, as Rewire recently reported. They want to know how big it is, how it compares to the guy in the cubicle (or urinal) next to them, and how big is big enough.

The first question is easily answered with a ruler and the last is highly subjective, but scientists in Britain now say they have the definitive answer to the middle questions: How does your penis compare to all the others?

A study released in the latest issue of BJU International, the journal of the British Association of Urological Surgeons, has compiled data on 15,521 men around the world and created the ultimate graph of penis size. The researchers did not get out measuring tapes themselves but instead reviewed existing studies on this topic.

Studies were included if they had at least 50 participants, if all participants were over 17, and if measurements were done by a health professional. Studies that asked men to measure their own penis and provide the information to researchers were omitted, as were studies that included men who had erectile dysfunction, congenital or acquired penile abnormalities (such as peyronies disease), or those complaining that their penis was too small.

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The average flaccid penis measures 3.61 inches in length and 3.66 in circumference, according to their findings. When erect, the average penis is 5.16 inches long and 4.69 inches around.

Remember, these are averages, which means there is a wide range of sizes. The researchers plotted the results on a nomogram (or graph) that shows what percentile each measurement falls into. A look at the nomogram shows, for example, that when erect 68 percent of men fall between 4.5 and 5.8 inches, and 95 percent of men measure between 3.9 and 6.5 inches.

The authors say they took on this challenge to help health-care providers and men themselves. Co-author Gordon Muir, a urological surgeon at the Kings College Hospital NHS Foundation Trust in London, told the Huffington Post in an email, “We wanted to be able to help men and their doctors with a definitive paper since there are many contradictory reports from small or poor quality studies. Many men live lives of misery and shame, or undergo harmful and unproven interventions, due to a false belief they are abnormal.”

Muir and colleagues, however, are unsure if showing the nomogram to men would help or hurt. They worry that, even if they understand the math behind averages, those who measure under the average will feel inadequate or defective.

“Comparing one’s self and one’s attributes against others is a ‘double-edge sword’ and may confirm perceived inadequacies,” the researchers wrote.

The results also found no correlation between penis size and characteristics such as height, race, finger length, body mass index, and testicular volume. Muir told Reuters he hopes this will help men realize that there is “no right size penis for a man of any height, just a range of normal.”

Correction: A version of this article incorrectly stated that the average penis sizes found by the study “[mean] that 50 percent of penises are bigger and 50 percent are smaller.” We have corrected this information and regret the error.

Topics and Tags:

Penis, penis size, Sexuality