Is Your Penis Normal? There’s a Chart for That

This article was originally posted on RealClearScience.

Are you one of those men who constantly worries that your penis isn’t of an adequate size? Then you may be suffering from “small-penis syndrome.” (Yes, that’s an actual medical term.) More likely, you are simply intrigued to know how your manhood measures up against the rest of humanity. Either way, whether you are anxious or merely curious, you may soon be able to ask your doctor to pull out a tape measure so he can definitively answer the question, “Hey doc, is my weiner big enough?”

British researchers, led by Dr. David Veale at King’s College London, conducted a meta-analysis of the English language literature on penis size. They screened 16,678 publications and, based on various criteria, whittled the list down to 17 studies. (For example, studies that examined patients with erectile dysfunction were eliminated.) From these studies, the authors extracted data on the length and circumference (“girth”) of both flaccid and erect penises from 15,521 men. This information was used to simulate 20,000 observations.

The following data represents the “average penis”:

Flaccid length: 9.16 cm (3.61 in)
Stretched flaccid length: 13.24 cm (5.21 in)
Erect length: 13.12 cm (5.17 in)
Flaccid girth: 9.31 cm (3.67 in)
Erect girth: 11.66 cm (4.59 in)

The authors also constructed a handy chart:

As shown, 95% of erect penises fall within the range of 9.8 cm (3.86 in) to 16.44 cm (6.47 in). Also, it is interesting to note that the stretched flaccid penis is quite similar in length to the erect penis.

Disappointingly, the authors were not able to draw any conclusions on penis size and race. However, it should suffice to say that the rumors are probably true.

Finally, it is worth mentioning that some dudes really do have puny peckers. Like IQ, penis size falls along a normal distribution, and penises that are two standard deviations below average are considered, by definition, to be small. (However, men with “micropenises,” which are 2.5 standard deviations below average, constitute merely 0.14% of the population.) Similarly, there are lucky guys out there who have penises that are two standard deviations above average and are considered, by definition, to be blessedlarge. The other 95.45% of men, who fall within two standard deviations of the average, have boringly normal penises.

So, worry not, manly men. The vast majority of you are perfectly normal. Well, except that guy with two penises. That’s definitely not normal.

Source: “Am I normal? A systematic review and construction of nomograms for flaccid and erect penis length and circumference in up to 15,521 men.” David Veale, Sarah Miles, Sally Bramley, Gordon Muir, and John Hodsoll. BJU International; Published Online: March 3, 2015 (DOI: 10.1111/bju.13010).