Many men (and women) are curious about the average penis size, but Dr. Abraham Morgentaler took it to the next level. He conducted a study on over 15,000 men to create a chart of the average size – and the good news is, you’re probably better off than you think.

penis size average

“Most men tend to believe they’re smaller than average, and there’s some distortion about what reality is,” says Morgentaler, director of Men’s Health Boston and author, most recently, of “The Truth About Men and Sex: Intimate Secrets From the Doctor’s Office.”

The study basically reviewed and summed up all the previous studies documenting penis size and girth; in the end, Morgentaler ended up with 15,521 data points from participants aged 17 to 91, who’d had their penises measured in 20 previously published studies carried out in Europe, Asia, Africa and the United States. According to the study, just 2.28 per cent of the male population have an abnormally small penis and 2.28 per cent have an unusually large one – the rest fit into a general curve, slowly dipping up.


The study found that the average length during erection is 5.16 inches (13.12 centimeters) and the average flaccid length is 3.6 inches (9.16cm). As for the girth, the average value is 4.59 inches (11.66 cm) when erect, and 3.66 inches (9.31cm) when flaccid. What’s interesting is that if your penis is 11 cm, then you are in the low 10 percent – but if your penis is just 4 cm longer, that puts you in the high 15 percent – quite a significant jump for such a small difference, which seems to indicate that most penises are rather similar in size.

penis size average

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I have some even better news: the real average value might even be smaller than this study suggests. The studies were mostly conducted on volunteers, and there’s a good chance that those volunteers were quite confident in their characteristics(and therefore above average). But this is the best data we have.

“What’s interesting is, when you look at the curves, you see that most penises actually are fairly similar in size,” Dr. Morgentaler says. “You really have to go to the extremes — the top or bottom 5 or 10 percent — to really see some big differences. And truthfully, in my practice, I would say that’s exactly right. Most men have penises roughly the same size.”

Psychiatrists who carried out the study said they hope the findings could help men suffering from “small penis anxiety”. In his 26 years of experience as a urologist, Dr. Morgentaler has seen thousands of patients, and “probably there hasn’t been a single one who hasn’t paid attention to his penis size on some level,” he says. He also wants to dispel some of the commonly held myths regarding the male reproductive organ. For instance, the old myth is false — there’s no correlation between foot and penis size, nor is there between the penis and other extremities.

The study also found no correlation between penis size and race, but the majority of participants were European and Middle Eastern so it was quite difficult to make a thorough assessment.

Journal Reference: David Veale, Sarah Miles, Sally Bramley, Gordon Muir and John Hodsoll. Am I normal? A systematic review and construction of nomograms for flaccid and erect penis length and circumference in up to 15 521 menDOI: 10.1111/bju.13010