The Real Science Behind Penis Size and Race

Earlier this year, an infographic that ranked 88 nations by their populations’ purported average penis sizes—data drawn from 40 studies—did the rounds of lifestyle publications and tabloids. This coverage stirred up a few literal dick-measuring contests and a slew of dumb jokes on social media. It also affirmed widespread beliefs about racial differences in penis sizes. Although the graphic gave Ecuador top placement in its rankings, most of the longer-ranked nations were in sub-Saharan Africa, while East Asian nations got short shrift at the bottom of the chart.

Few people batted an eye, though—probably because graphics or listicles conveying similar “findings” crop up every few years. And these stories only confirm what many already assume must be true, as we see so many people uncritically endorsing these stereotypes (think: big Black dick tropes in porn or comedians who quip about Asian male endowment) but rarely encounter public pushback against them. When people do push back against these stereotypes, some folks accuse them of knee-jerk, unscientific PC policing.

But these articles frustrate the small circle of people who actually study penis size to no end. For starters, when you dig into these infographics, listicles, and quick-hit write-ups, you’ll quickly find they’re all based on flawed data—usually small, non-representative studies using notoriously unreliable self-measurements and reporting.

There’s not much high-quality research on average penis sizes overall, says Alicia M. Walker, a sociologist at Missouri State University who’s studied this issue. Based on this limited data, most sexual health and development experts will tell you there may be slight differences between penis averages across racial lines—although we can’t say so for sure. However, the slight differences that do appear in some studies are negligible and likely misunderstood. We also know that these ill-founded stereotypes can be harmful, as they fuel rampant objectification of some men, desexualization of others, and sexual anxieties galore. 

So where did the notion that there exist massive racial differences in penis size come from? Plus, how and why do we keep perpetuating it if there’s no clear support for dick stereotypes in the scientific literature or the real world? To the surprise of almost no one, the answer appears to be a heady mixture of bigotry, stunted sexual discourse, and the poor track record some elements of the media have when it comes to assessing and presenting so-called scientific stories.     

Origins of penis size stereotypes

Modern racial penis stereotypes date back to at least the 15th century, when European explorers in sub-Saharan Africa commented on the local men’s supposedly enormous genitals in their travelogs. Some modern readers seemingly take these tales at face value. But these accounts actually seem to reflect the ancient Greek belief that a big, erect dick was a sign of animalistic, uncontrollable sexuality while a small penis was a sign of civilized restraint and rationality—a notion that endured and spread through Roman philosophy, medieval Christian art, and ultimately early modern proto-science, thanks to Europe’s eternal hard-on for all things Grecian. 

Those explorers’ accounts fit a longstanding tradition of mapping this trope onto cultures that an observer saw as lesser than their own, to justify a sense of inherent small-dicked, hyper-civilized superiority. And this peculiar form of othering flowed directly into the Atlantic slave trade, as white people used the notion of the well-endowed and thus uncivilizable, unpredictably virile Black man (see: the mandingo archetype) as a justification for absolute dehumanization and control. The same notion fueled lynch mobs in the Reconstruction South, and it’s still a key talking point for modern racists. 

“Most research attempting to discern racial differences in penis size relies upon pseudoscience from scholars of race realism.” —Alicia M. Walker

This stereotype persists even outside of overtly racist circles because it’s been laundered into mainstream discourse over the course of centuries—and in recent years, it’s been endorsed by many Black men as well.

As Herbert Samuels, a sex educator who specializes in Black sexual experiences, points out, this is one of the only widely accepted Black stereotypes that’s now seen as a positive (by everyone aside from old-school racial science advocates, that is), so it’s only natural for folks to take it and run with it. (No one is sure when or how old ideas about small dicks faded and our modern obsession with massive members emerged. The few folks who’ve studied this issue just suggest that many people always preferred big dicks in their personal lives, and that preference gained cultural traction as old philosophies fell out of fashion.) Periodically, prominent Black figures step up to explain how this stereotype has led people to oversexualize and thus still dehumanize them. 

Tellingly, East Asian men were historically portrayed as virile sexual threats to white women, too, right up into the early 20th century, when Japanese actor Sessue Hayakawa, an early Hollywood heartthrob, played an irresistible wife-stealing neighbor in Cecil B. DeMille’s The Cheat. Only after racist laws and social pressures pushed East Asian men in America into stereotypically feminine jobs like laundry and cooking—and with the rise of mid-20th century anti-Japanese propaganda—did American culture recast Asian guys as ill-endowed, effeminate non-threats. 

Although few Asian American men believe or endorse this stereotype themselves, it has an incredible amount of cultural traction, worming its way into crass jokes on The Bachelorette and commentary on 2010s NBA star Jeremy Lin in recent years, for example. (It’s also largely responsible for the conspicuous lack of Asian American male talent in Western porn until fairly recently.) And many men with East Asian heritage say it’s explicitly played a role in their ability to find sexual partners on apps. 

These stereotypes create a conspicuous Goldilocks zone, writes psychologist Scott A. McGreal, “in which European men are ‘just right’” in their mix of masculinity, self-control, and penile dimensions. Given that white people were the ones who first recorded and led the charge in perpetuating these penile beliefs, he points out, this is all far too convenient to take at face value. 

Historical research on penis size and race

Scientists have been trying to measure dicks for decades, and their study isn’t a matter of puerile or idle curiosity. These measurements help us understand more about sexual development and health. They help us improve the fit and comfort—and thus the use and efficacy—of condoms. And they’re valuable tools for helping men with sometimes crippling body image issues. 

“As one of the few researchers to attempt a study about penis size, I frequently receive requests from strangers to evaluate their penis,” says Walker. “During my study, men shared heartbreaking tales of avoiding doctors for decades out of fear of disrobing, avoiding intimacy for the same reason, and even attempting suicide because they were convinced their penis was inadequate.” 

“For the record, I provide no such [evaluation] services,” she adds. 

But the more we try to study penis size, the more we learn that measuring dicks is a surprisingly tricky matter: You can’t rely on self-reporting, for starters. That’s what the pioneering but notoriously methodologically sloppy American sexologist Alfred Kinsey did—and he got averages about an inch longer than any study that relies on independent, clinical measurements. (Kinsey’s bad data is actually why so many men believe the average penis is six inches long. This, alongside penis enlargement ads, is a huge reason penile size anxiety is so rife these days.)

When a researcher measures an erect penis, though, how should they account for curvature or long foreskin? Do they measure from the top or the bottom? How far into the pubic fat, or below the scrotal line, should they measure, and how can they be consistent in prodding into that fat or identifying that line? How can they account for the fact that not every erection is equal in size—and a cold lab and clinical measurement will certainly tip that scale? They could inject subjects’ penises with fluids to make them consistently fully engorged. But is that an accurate measurement of penises in the wild? They could stretch flaccid penises. But how can they account for the effects the frequency or intensity of stretching seems to have on measured length? For that matter, how can they deal with the selection bias inherent in finding people willing to strip down and researchers poke and prod at their genitals for a study like this? 

“On top of all that,” Walker adds, “there are political and social issues. My own study [started in 2018] was years in the making because of such challenges. Public outcry was substantial because I was a woman studying penis size. Never mind that my research assistant was a man.” 

Given these uncertainties, most serious penis size researchers will tell you that we don’t know the global average erect penis length (though most modern studies seem to agree it’s likely somewhere between 5.2 and 5.5 inches). It’s even harder to answer questions about racial differences in average size “with any degree of scientific certainty,” as sex researcher Justin Lehmiller put it in a 2018 analysis of the existing evidence. Most robust studies on penis size have looked at overwhelmingly European or Middle Eastern populations. Few made it a point to control for or compare racial groups. And even studies that do have their limitations. 

We certainly didn’t have any meaningful know-how on consistently and fairly measuring penises, much less robust studies on global and demographic-specific erection averages, when clearly biased European observers first came up with then perpetuated racial penis size myths. 

The enduring challenge of measuring dicks, and the dearth of strong data, is why most graphics and listicles on national or racial differences default to using poorly-designed, small studies that rely on self-reported data: It’s all that’s available. All of these weak studies also use seriously different sampling, self-reporting, and analytic methods. As such, they basically compare bad apples to bad oranges, explains Walker. They are—I cannot stress enough—total BS.

“People throw data around online like it’s trash. Nobody is checking it, and it filters down into society and creates more anxiety and racism.” —Xtine Milrod

Some compilations of bad, weak data are byproducts of content creator ignorance or sloppiness. “Not to bag on journalists,” says Xtine Milrod, a psychologist and therapist who specializes in sex and sexuality issues, “but in my years as a researcher and clinician, I’ve spoken to a lot who absolutely botch their reports on studies’ results. People throw data around online like it’s trash. Nobody is checking it, and it filters down into society and creates more anxiety and racism.”

But far too often, people also intentionally compile and peddle bad data to reinforce racist tropes. Walker points out that race realists—people who believe “innate biological differences between racial groups exist in intelligence, personality, social behavior, and physicality”—have had a thumb on the scale of penis size research for decades. 

Notoriously, Canadian psychologist and race realist J. Philippe Rushton published high-profile papers in academic journals in the 80s and 90s arguing for the existence of fundamental biological racial differences. One of his pet theories was that Black men developed large penises and sex drives but smaller brains because their environment pushed them towards higher rates of reproduction, while Asian men developed larger brains and smaller penises—and white men like himself got nature’s perfect dick-to-brain balance.

(The notion that penis size correlates to sex drive has no basis in the science of human sexual development or libido, so Rushton’s work was pseudoscientific trash from the get-go.)

To push this case, Rushton relied on data like folk tales and sketchy, anonymous 18th-century European anecdotes, which he laundered into the public consciousness as reliable data points. Despite the glaring flaws in Rushton’s work, even recent studies—like a high-profile paper on penis size from 2013 that looked at racial differences—still build on, and at times explicitly attempt to validate, his ideas using their own bad data. 

“Most research attempting to discern racial differences in penis size relies upon pseudoscience from scholars of race realism,” argues Walker. Some researchers and reporters don’t even realize the noxious ideas they’re perpetuating by citing these studies. Others, however, absolutely do. 

Current science on penis size

So what does the scant research produced by people who aren’t overt racists say about race and erections? Well, over the last decade, meta-analyses of dozens of well-conducted studies have found differences in average penis length, with Black people at the longer end, East Asian folks at the shorter end, and white guys right in the middle. But the widest differences are on the order of less than half an inch. (The recent penis sizes of that world infographic showed a spread of almost three inches, by comparison.) As one team of American researchers put it in a 2015 paper, “although we observed some racial and ethnic differences… the magnitudes of the differences were insufficient to justify” stereotypes about racial differences in penis size. 

“The differences reported are quite small,” Walker stresses. “They don’t warrant attention.” 

What’s more, most researchers note there’s so much variation in erectile length within any group that these averages are functionally meaningless for most people’s everyday experiences. 

Sexual health researchers also point out that, while genetics play a role, a slew of factors can influence penis size—which is why, in twin studies, people with the same genetics sometimes wind up with different erections. Notably, hormonal exposure, nutrition, and medical issues that arise between fetal development and puberty can influence sexual development. Changes in our diets may, some researchers believe, explain why a recent massive study that tracked penile length over almost eight decades found a notable increase in the length of the average erection over time, for example. These environmental factors may also explain why a few studies have found notable differences in penile size averages between East Asian and Asian American men.  

While the fraught history of this tiny field of study, and the limitations baked into even robust research, mean that we both cannot and should not make any firm claims about race and penis size, these complications don’t mean we should stop looking into the issue.

The penis size researchers VICE spoke to for this article argued that we actually need more research on demographic variations in penis size. Probing this topic could help us learn more about the role of factors like lifestyle and environment play alongside genetics during sexual development. It’s also, Milrod argues, probably the best antidote to the stereotypes that older, less thoughtful, and responsible research and commentary have helped to embed within our collective social psyche. Because when you walk people through solid data on average erectile length—and what a few fractions of an inch really looks like—Milrod explains, “they begin to understand this is a cultural issue, not an anatomical one”.