How Big is the Average Penis? The Science of Size!

Size matters? Perhaps but it certainly can be a major downer if you feel you are far below average. Previous studies weren’t very scientific because it turns out they were mostly based not on a short arm inspection with a ruler but were data gathered by self-reporting, or, in less scientific terms, male bragging.

Strangely enough it took decades for “scientists” to acknowledge this giant hole in their data, saying in a recent report, “Self-reporting, which doesn’t always yield reliable results. People tend to overestimate themselves,” according to David Veale, a psychiatrist at the South London and Maudsley NHS Foundation Trust. Dr. Veale was quoted at the beginning of a very scientific article in the March 3rd issue of Science, the peer-reviewed journal of the AAAS.

BTW, don’t bother looking at his shoes.

In the British Journal of Urology International, a new study synthesizes data from 17 previous academic papers that included measurements from a total of 15,521 men from around the world. The data enabled the researchers to calculate averages and model the estimated distribution of penile dimensions across humanity. “It still just strikes me how many men have questions and insecurities and concerns about their own penis size. We actually do need good data on it,” says Debra Herbenick, a behavioral scientist at Indiana University, Bloomington, who was not involved in the study.

Dr. Veale blames porn casting agents because male performers are often selected for their extremely large genitalia. Also to blame are probably the spam flooding email boxes trying to sell fake enlargement methods/drugs by claiming 17.78 cm (7 inches) is average for an erection.

Actually that length is found in the general population about as often as you find Mensa-qualified individuals, that is, a 7-inch member would place its owner in about the 98th percentile, the same percentage of the population measured with genius IQ’s.

The article also reminds people that when it comes to enlarging your horizons, “Veale says, There are no effective lotions or potions or pills.”

According to the team’s analysis, the average flaccid, pendulous penis is 9.16 cm (3.61 inches) in length; the average erect penis is 13.12 cm (5.16 inches) long. The corresponding girth measurements are 9.31 cm (3.66 inches) for a flaccid penis and 11.66 cm (4.59 inches) for an erect one.


That means the actual average size of 5 inches is 2 inches or nearly 30% shorter than the 7-inch claim made in many spams and ads trying to sell fake enlargement products.

The study also deflates an old wives tale that equated foot size to the size of the pleasure tool.

It turns out that the only thing big shoe size means is that either the gentleman is a clown or that he has big feet.

The study also found no correlation between race and the size of a man’s member, although the researchers acknowledge the subjects were mostly Caucasian.

Science| DOI: 10.1126/science.aaa7934