Average Penis Is Less Than Six Inches Long, Study Finds


A new study published in the Journal of Sexual Medicine has found that most men are not endowed like Dirk Diggler from Boogie Nights. In fact, most men have a penis that measures less than six inches long when erect.

The study, led by Indiana University researcher Debby Herbenick, surveyed 1,661 men, each of whom was asked to measure both the length and girth of his penis when erect. Men were also asked to tell the researchers how they attained the erection.

The largest penis in the survey measured in at 10.2 inches, while the smallest was 1.6 inches. Most men fell firmly in between, with the average penis measuring 5.6 inches in length and 4.8 inches in girth. The researchers found that characteristics such as race or sexual orientation were not good predictors of penis size.

However, men who reported attaining their erection through oral sex were on average larger than men who were alone when they became erect. Herbenick told LiveScience, “We don’t know if that means that when men have oral sex that it’s more arousing and they get a bigger erection, or means that men who have bigger penises could be getting more oral sex in the first place.”

The data was collected as part of an earlier study comparing men’s use of a standard-sized condoms to the use of condoms specifically sized to fit their erect penis. Herbenick explained the results of that study to RH Reality Check, saying, “We found that both standard and fitted condoms were comfortable for most men, and that some men on either end of the size continuum preferred condoms fitted to the size of their erect penis. Currently, ‘fitted’ condoms are no longer on the U.S. market. However, there’s a wider-than-ever range of condoms that are safe, effective, and pleasurable and that are available for men and their partners to choose from.”

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