The Last Word on the Length of Men’s Erections

Do erections actually measure 10 inches? Stories on sexually explicit sites are filled with men with eight-, nine-, or 10-inch erections, or even longer. Of course, most people know that erotic fiction indulges in vast exaggerations.

In surveys asking men how large they’d like their erections to be, the answers are generally around 7.3 inches. Meanwhile, several studies have established an average that’s considerably shorter: 6.2 inches.

Is even that 6.2-inch figure accurate? Not according to a researcher at Clemson University in South Carolina, who recently analyzed “all known studies” of erection length—22 published reports—and found that the average erection measures 5.1 to 5.5 inches, and “probably toward the lower end of this range.”

Who Measures?

The official way to measure erection length is on the top side of the shaft, from the pubic bone to the tip. In some studies, men have measured themselves. In others, researchers have wielded the rulers. Not surprisingly, when men measure, erections come out larger than when researchers do. Men tend to jam the ruler into their abdomens and pull on their erections to stretch them.

Self-measurement studies began in 1948 when pioneering sex researcher Alfred Kinsey asked thousands of men to measure their erections. Their reported average was 6.2 inches. Kinsey's finding played a major role in establishing that supposedly average length. Other self-report studies involving heterosexual men have produced similar average lengths: 6.1, 6.2, or 6.3 inches. Meanwhile, self-measurement studies by gay men have averaged 6.5 inches—but the findings were shorter when their partners measured.

It seems certain that self-measurement studies have produced exaggerated findings. The Clemson researcher argues that the errors have resulted from two predictable, very human errors:

• Volunteer bias. Men who believe they have small erections don’t rush to measure them and send the results to researchers. In Kinsey’s study, only half the men who could have replied actually did, presumably those who considered themselves the best-endowed. This undoubtedly raised the average.
• Social desirability bias. This error involves the tendency to answer questions with replies the respondents believe are culturally expected. For example, many studies show that people overestimate how much they exercise. Culturally, exercise is considered beneficial, so people tend to exaggerate their time spent in physical activity. Similarly, people underestimate how much alcohol they drink. Culturally, heavy drinking is problematic, so people understate their consumption. What do men expect for penis size? Somewhere between enormous and gargantuan. Consequently, they tend to exaggerate the length of their erections.

When researchers have measured erection length, findings have been consistently smaller—5.0, 5.1, 5.4, and 5.9 inches—or an average of 5.4. In other words, compared with self-measurement, researchers find erections to be around an inch shorter. Hence, the Clemson investigator’s finding that the most rigorous studies show an average erection length of 5.1 to 5.5 inches.

What Women Really Think of Erection Length

Several studies have asked women how long they believe their men’s erections are. Their average estimate: 5.3 inches, within the range the Clemson research found.

But are women happy with that? Researchers at UCLA and Cal State Los Angeles posted a survey on MSNBC.com that asked women what they thought of their men’s erections. A large number replied—26,437 women age 18 to 65. Seven out of eight (84 percent) said they felt “very satisfied” with their partner’s size. One in eight (14 percent) wished for larger and one in 50 (2 percent) desired something smaller. Most women value warmth, caring, kindness, consideration, solvency, supportiveness, shared values, and a good sense of humor over erection length.

The Male-Female Orgasm Gap

Why do men want gargantuan erections? Largely because they believe they are more likely to please women. This follows from men’s widely held belief that intercourse is what brings women to orgasm. If that’s true, then the longer the erection, the deeper it extends into the vagina, and the more likely women would be to climax. Actually, this belief is totally false and has caused a great deal of sexual misery.

Intercourse brings men to orgasm around 95 percent of the time. Most men assume the same is true for women. But the best research shows that only a small fraction of women are able to work up to orgasm from intercourse alone. The studies disagree, but it’s safe to say that fewer than 20 percent of women—and probably fewer—are reliably orgasmic solely from intercourse.

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Why is there such a pronounced orgasm gap? Largely because only a minority of men understand that most women need direct clitoral caresses to work up to orgasm. Many women don’t receive sufficient clitoral massage and cunnilingus to get there. Any size erection can bring great pleasure to the man it’s attached to. But the key to women’s pleasure is direct, gentle, extended clitoral caresses.

A small proportion of men—2 to 3 percent, or one in 30 to 50—actually do have huge erections, a group that includes many actors in commercial pornography who are hired in part based on their size. Consequently, the mostly male porn audience sees erections that are much larger than average. Porn misleads men into thinking that huge erections are the norm, while, on the contrary, the average erection measures around 5.1 to 5.5 inches. The vast majority of men have erections in that range, and the vast majority of women feel fine about it.