Everything on one ruler

Reading the extrapolations. Veale's pooled data gives a mean and standard deviation for both dimensions: erect length 13.12 ± 1.66 cm, erect circumference 11.66 ± 1.10 cm, with flaccid figures of 9.16 ± 1.57 cm and 9.31 ± 0.91 cm. Both distributions are close to normal, so any length converts to a percentile, and that percentile reads back off the circumference curve. A 6.61″ stretched length sits about 2.2 standard deviations up, so it is drawn with a circumference 2.2 standard deviations up: 5.55″.

Falcon's claim is drawn faintly for a reason. Every row carries a girth figure, so Falcon carries one too — about 10″ around. Treat that as arithmetic rather than anatomy. Length and girth are only weakly correlated in real men, and girth varies far less in absolute terms, which is why short-and-thick and long-and-thin are both common. Extrapolating twelve standard deviations out is an extension of a curve into territory where no data exists. Barr's row uses the girth he reports himself, 21.5 cm (8.46″), from a measurement that has never been published.

Condoms. Magnum XL is the largest Trojan makes: 180–200 mm long, 58 mm wide at the base, so cut for about 4.57″ of girth; other brands sell stock condoms up to 72 mm wide. The regular Magnum is 55 mm. At the other end, the narrowest mass-market condom is Japanese — Sagami's Xtreme Cobra, 44 mm at the base and tapered out to 53 mm at the head, which works out to roughly 3.46″ of girth at the base. Japanese sizing runs narrower across the board (49–56 mm versus the Western 52–56 mm), and India's Kohinoor sits in the same range. Anything smaller than that is custom-fit only, which is where the smallest condom bar comes from: myONE's 45C, 120 mm long and 45 mm wide (myONE took over TheyFit's custom range). Remember a condom is cut longer than the penis it fits, so the long condom bars aren't claims about anyone.

What the ordering shows. Sorted by length, the clinical measurements bunch tightly between about 5.0″ and 5.6″ — injection studies from San Francisco and Tel Aviv, the men's health clinic's stretched lengths, Veale's global average, Herbenick's self-reports. Everything above 6″ on this chart is either a preference, a guess, an old self-report, a condom, or a record. The 3rd-to-97th-percentile spread for erect length, which covers 94 men in 100, is 3.94″ to 6.39″.

The dildo rows are a revealed preference, with an asterisk. The best-selling realistic dildo across six US retailers measures 16.7 cm insertable and 12.7 cm around — 6.57″ by 5.00″ (Isaacson 2017). Length runs about one standard deviation above real erect length; girth lands almost exactly on it. The asterisk is that length is not actually a preference signal at all. Johns and Bushnell (2023) analysed 265 products against their sales popularity at the UK's largest retailer and found insertable length — averaging 7.07″ across the catalogue — had no significant effect on how well a product sold. Circumference did, and the effect ran negative: wider toys sold worse. So the length plotted here is what the market offers and people tolerate, while the girth is what they choose. The same study's authors noted manufacturers do not appear to design around anatomy or preference.

What women think the average is: 5.76″ by 4.50″. Prause's participants answered this question too, but the paper only plots it as a scatter (its Fig 3) without printing a mean, so this row is computed from the study's own raw dataset, which the authors released on Figshare. Recomputing the two published preference figures from the same file returns 6.41″ × 4.97″ and 6.37″ × 4.83″, matching the paper's 6.4 × 5.0 and 6.3 × 4.8, so the mapping is sound. The result is more interesting than the usual telling: women overestimated length by about 0.6″, but their girth estimate of 4.50″ came in slightly under the real 4.59″. The "everyone thinks it's bigger than it is" story holds for length only.

What isn't here, and why. The same questionnaire asked each woman for the smallest and the largest penis she had personally had intercourse with. Those two answers appear in the paper only as a scatterplot, and they were not included in the released dataset, so there is no number to plot without inventing one. What the paper does state: the models on offer ran 4.0″ to 8.5″ in length and 2.5″ to 7.0″ in girth, and women's choices for their smallest and largest partners showed no floor or ceiling effects — so their real range sat inside those bounds rather than pressing against them.

Gay and straight, with a large asterisk. Bogaert and Hershberger mined the Kinsey archive (5,122 men) and found 6.14″ × 4.80″ for heterosexual men against 6.46″ × 4.95″ for homosexual men — about 0.32″ and 0.15″, roughly a fifth of a standard deviation. It has never been tested by a clinician. Every replication uses the same instrument, and note where both bars sit on this chart: a full inch above every measurement a urologist ever took. Both groups are inflating; the entire question is whether they inflate equally, and a 2018 study found self-reported size correlates with social-desirability scores. Bogaert argued the two groups exaggerate alike, but asserted it rather than measured it.

The other side of the fit problem. Barnhart's MRI study of 28 women put the resting vagina at 6.27 cm deep — 2.47″ — with the introitus 2.62 cm across, about 3.24″ around. It lengthens substantially with arousal, though no modern study has measured by how much (the classic 1966 figure of 11–12 cm was taken with a speculum in place), and the canal is elastic in a way no static number conveys. But set the resting figures against the average erect penis at 5.17″ by 4.59″ and the picture is plain: the average penis already exceeds the resting depth by a wide margin, and cast studies found resting canals running from 2.70″ to 5.83″. Length past a certain point has nowhere to go, which is the anatomical version of the condom observation — everything in this subject is built longer than the thing it meets.

The men who paid to be made bigger were normal. Mondaini examined 67 men who came to a Florence andrology clinic asking for lengthening surgery. Not one fell below the 2.5th percentile of the nomogram his own group had built from 3,300 conscripts, and none had any anatomical abnormality. They did skew small within the normal range — 60% sat between the 5th and 25th percentiles — but the striking number is what they believed: asked to estimate a normal flaccid penis, they said 12 cm. The real flaccid average in their own reference population was 9 cm. They overestimated by a third, and 37% traced the worry to seeing pornography as teenagers. After being shown where they actually fell on the nomogram, 72% no longer wanted surgery.

A ceiling, for once. Isaacson's team reached the only evidence-based "too big" figure in this literature from an unexpected direction: transgender men seeking revision surgery because their neophallus girth made intercourse impossible. Working backwards from bestselling dildos, they recommend a neophallus no wider than 15.1 cm around (5.94″) after prosthesis — two standard deviations above natal girth — with a conservative target of 13 to 14 cm. Their four index patients averaged 17.6 cm, four to five SD out. The row here is plotted at average length, because the guideline is about girth alone.

Regions differ by less than men do. Mostafaei pooled 33 clinician-measured studies and 36,883 men by WHO region. The largest regional average for stretched length was the Americas at 14.47 cm (5.70″); the smallest was the Western Pacific, though the paper describes that qualitatively rather than printing a figure, so the low anchor here is a 301-man Indian study at 10.88 cm (4.28″). That is the full between-region spread: about 1.4″. The within-population spread, 3rd to 97th percentile, is 2.8″. Where a man lives tells you about half as much as his own variation does — and the pooled global average from this study, 12.84 cm stretched, sits within 0.4 cm of Veale's and Belladelli's.

The difference between two ways of holding a ruler is bigger than most of the differences on this chart. Bone-pressed means the ruler is pushed into the fat pad until it meets the pubic bone; non-bone-pressed means it rests on the skin. Pooling every study that reports each, calcSD gets 14.00 cm bone-pressed against 12.13 cm non-bone-pressed — 5.51″ versus 4.78″, from 3,138 and 2,766 men. That 0.74″ is larger than the gay–straight gap, larger than the men's health clinic gap, and about equal to the entire gap between clinician measurement and self-report. Veale's 5.17″ pools both conventions, which is why it sits between the two new bars. Any figure quoted without saying which convention it used is ambiguous by roughly three quarters of an inch.

Injection studies do not agree as tidily as this chart once suggested. An earlier version carried a row sourced only as "a pharmacological study of 278 men." Checking calcSD's list of every injection study it holds, no such study exists — the figure came from a secondary summary and could not be traced to a paper, so it has been removed. The four rows that remain are all named, and they span 5.07″ (Wessells, San Francisco) to 5.92″ (Salama, Egypt), with the best-powered of them — Habous, 778 men — at 5.65″. Part of that spread is convention: Wessells published a non-bone-pressed figure, and the same 80 men measured 6.20″ bone-pressed. The rest is real disagreement between populations and clinics. Injection settles whether the erection is full. It settles nothing else.

Two studies worth having for what they show about sampling. The LifeStyles condom study had nurses measure 300 volunteers at spring-break events in 2001, and produced 5.88″ by 4.97″ — the highest clinician-measured average anywhere, from men who queued up to be measured in public. And 1,383 members of r/BigDickProblems self-reported 7.28″ by 5.60″. Neither is wrong about the men it measured. Both are useless as population estimates, and together they bracket how far a number can drift on sampling alone before anyone misreports anything.

How the normalised view works. Ten of calcSD's studies measured the same men both ways and published both figures, so the size of the correction isn't guesswork. Within a single study the erect gap runs from 1.10 cm (Son 1999) to 2.85 cm (Wessells 1996), clustering near 2 cm; pooled across everything that reports each convention it is 1.87 cm for erect, 1.69 cm for stretched and 0.57 cm for flaccid. Those pooled figures are the shift applied here, except where the study published its own bone-pressed number, in which case that real figure is used instead. Wessells is the case that matters: the 12.89 cm everyone quotes is the non-bone-pressed measurement, and the same 80 men measured 15.74 cm bone-pressed — 6.20″. Seen that way the "tight cluster" of injection studies was partly an artifact of which convention each paper happened to report.

What can't be normalised. Veale's nomograms pool both conventions in an unstated ratio, so every percentile bar drawn from them — the backbone of this chart — sits in the normalised view as an outline rather than a corrected bar. The same goes for Belladelli's temporal figures and Mostafaei's regional one. That is not a gap in the method; it is the finding. The most-cited numbers in this field are ambiguous by about three quarters of an inch, and no amount of arithmetic recovers which convention each contributing study used. Rows where the convention was never stated at all — Kinsey and the Bogaert comparison — are left out of the normalised view entirely rather than guessed at.

What gets a row, and what doesn't. This is not a meta-analysis and does not try to be one. A measurement earns a bar if it anchors a category nothing else here covers — a method, a convention, a population, a product class — or if it is the best-powered example of its category, or if it demonstrates a failure mode worth seeing. A study that merely adds another estimate of something already anchored is left out, however good it is. That is why sixty-odd clinician-measured studies exist in calcSD's list and around a dozen appear here.

Why stretched Western length is on the chart. A recurring argument holds that 7″ is far more common than the calculators imply, citing Pereira 2004 (Portugal, 498 men), Solé 2022 (Argentina, 800) and Barboza 2018 (Brazil, 450), all of which found around 11% of men at or above 18 cm. The three studies are real and correctly measured. They are also all measuring bone-pressed stretched length, and the comparison is usually drawn against an erect distribution. Against the pooled Western stretched figure — 15.45 cm across 3,767 men, which already contains all three studies — about 10% are expected at or above 18 cm, against the 11% observed. The discrepancy is roughly nothing. Fit a normal curve to Pereira's own mean and standard deviation and it predicts 1.4 men at or above 21 cm where 2 were found. The tails behave; it is the means and the conventions that differ. Rather than three near-identical rows, the chart carries the aggregate that contains them — and it sits nearly an inch above Veale's mixed-convention stretched bar, which is the point.

Kinsey's extremes still aren't here. His men mailed in their own numbers on cards, and the outer values were never published in a usable form, so the Kinsey row remains an average. The real extremes on this chart come from Herbenick 2014, the only large study to publish its range: 4 cm to 26 cm in length, 3 cm to 19 cm in girth, and those are different men at each end.