What Is the Average Penis Size?

Whether it's big, small, or just the right size, the penis carries a lot of weight when it comes to a person’s confidence in their sexual ability. Worries about having an adequate penis size are common. In one study, 68.3% of 200 men said they had concerns about their penis size. Societal pressures and inaccurate portrayal in the media generate unrealistic expectations about penis size, which drive anxiety and dissatisfaction.

Penis size generally does not affect sexual function, but those who are less satisfied with their penis size report more sexual health problems. Discomfort over penis size can therefore lead to relationship issues, low confidence, and erectile dysfunction. Those who are dissatisfied with their genital self-image are also more likely to feel uncomfortable to have others, including healthcare providers, look at their penis. Knowing what the average penis size actually is can help prevent unrealistic expectations from creating these problems.

Average Penis Size

The average length of an erect penis is 6 inches, while the average circumference (also called girth) is 5 inches. A flaccid penis, which is when a penis hangs soft, measures on average 3.61 inches with a circumference of 3.66 inches.

Penis size is not static, and can change temporarily with temperature. If a penis is exposed to cold temperature, a flaccid penis may shrink in size. That’s your body trying to protect the penis. Other factors, like age, will also result in penis size change.

Factors Influencing Penis Size

The size of the penis is influenced by the hormones during puberty, at typically between 10 and 14 years old. The penis may continue to grow until a person is 21 years old.

A person’s height, foot size, weight, and age have little to do with their penis size. Furthermore, diet, pills, and exercise do not influence the size or shape of the penis. In fact, the size of the penis can rarely be altered or enlarged. Surgery is a rare exception: penile length and erectile function are known to be reduced after pelvic surgery such as radical prostatectomy and can be improved with penile rehabilitation.

Penis pumps and vacuums, which draw blood into the penis to create an erection, create a stronger erection, but do not increase penis size. The penis is made up of erectile tissues, not muscles, and therefore cannot be strengthened.

Does Size Matter?

A 2015 study looked at cisgender women’s preferences for penis size and how they may influence cisgender men's comfort within their own body. Looking at photographs of erect penises, the women in the study preferred only slightly larger penises than the average size (6.4 inches).

It also looked at sexually active women and their preferred penis for a one-night stand compared to the preferred penis size for a long-term relationship. They preferred a 6.4-inch penis for a one-night-stand and a 6.3-inch size for a long-term relationship, which is not a big difference. Another study found that girth was more important than length, since it leads to more sexual satisfaction.

In a study published in the British Journal of Urology International, 85% of women were satisfied with the size of the partner’s penis, while the men were less pleased with their penis size. Approximately 45% of the men said that they thought they had a small penis, but small penises are incredibly rare. A micropenis is when a penis is less than 2.8 inches in length when it's erect. It affects only 0.6% of men.

The size of a penis can affect a cisgender men's sexual experience and performance through psychology. Since smaller penis sizes can result in low confidence, the person who thinks they have a small penis may not become as erect during sexual activities, prematurely ejaculate, or lack performance overall. Because of this, there is a stigma that surrounds smaller penis sizes as not performing as well as larger penis sizes.

Flaccid or Erect

Flaccid and erect penis sizes may differ. Individuals whose penis grows less than 1.5 inches when going from the flaccid to erect state are known as showers, while those that grow more than 1.5 inches are growers. A 2018 study found that the penis grew 1.5 inches on average for both groups.

Smaller flaccid penises lengthen at erection by a greater percentage than larger flaccid penises, with most men reaching an average size of 5 to 7 inches. The flaccid size of a penis is not a good predictor of erect size.

Healthy erections that lead to more length and girth have to do with tissue elasticity, genetics, collagen, and blood flow.

Problems with a Bigger Penis Size

A large penis is linked to higher infection risks, because it introduces more friction during intercourse from a condom, which can then introduce more bacteria into the vagina. The increase in friction may also lead to genital injury. A larger penis has been associated with high infection rates in men who have sex with other men as well.

How to Measure Penis Size

To measure penis size, simply use a ruler or a tape measure. When the penis is flaccid, measure from the tip of the penis to the area where the penis connects to the pubic bone. If the penis is erect, measure from the tip of the penis to the pubic bone. To measure the circumference, wrap a measuring tape around the middle of the shaft (the body of the penis). Compare the flaccid and erect penis measurements to find out the difference between the flaccid length and erect length.

A Word From Verywell

Many men are concerned or worried about their penis size falling short of their partners' expectation or if its size will impede any sexual pleasure for their partner. It's important to remember there is no “normal” when it comes to penis size. It’s as unique as the size of your nose or other parts of your body. A larger penis does not guarantee sexual satisfaction. A larger size, in fact, can carry a higher risk of infection.

If you’re concerned about your penis size and how it’s negatively affecting your sexual performance and self-esteem, talk to a doctor or a therapist. A physical exam can reassure you that your penis is healthy and sized normally. Counseling may help you work through your feelings.

Frequently Asked Questions

  • When do penises stop growing?

    Penises usually stop growing by the time a male completes puberty between age 18 and 21.

  • What factors influence penis size?

    Genetics play the largest role in determining penis size. However, other factors that may determine penis size include hormones like testosterone, which can be affected by nutritional choices and exposure to toxins. During puberty, the amount of testosterone can be increased with proper diet and exercise, which then influences the final penile length in adulthood.

  • Does ethnicity influence penis size?

    The short answer is maybe. Some studies have said that ethnicity influences penis size but the differences among various ethnicities were minimal.

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22 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Tiggemann M, Martins Y, Churchett L. Beyond muscles: unexplored parts of men's body image. J Health Psychol. 2008;Nov;13(8):1163-72. doi: 10.1177/1359105308095971

  2. Herbenick D, Schick V, Reece M, Sanders SA, Fortenberry JD. The development and validation of the Male Genital Self-Image Scale: results from a nationally representative probability sample of men in the United States. J Sex Med. 2013 Jun;10(6):1516-25. doi: 10.1111/jsm.12124.

  3. Johnston, L., McLellan, T., & McKinlay, A. (Perceived) size really does matter: Male dissatisfaction with penis sizePsychology of Men & Masculinity. 2014;15(2): 225–228. doi.org/10.1037/a0033264

  4. Prause N, Park J, Leung S, Miller G. Women’s preferences for penis size: a new research method using selection among 3d modelsPLoS One. 2015;10(9):e0133079. doi: 10.1371/journal.pone.0133079

  5. Veale D, Miles S, Bramley S, Muir G, Hodsoll J. Am I normal? A systematic review and construction of nomograms for flaccid and erect penis length and circumference in up to 15 521 men. BJU International. 2015;115(6):978-986. doi: 10.1111/bju.13010

  6. Siminoski K, Bain J. The Relationships Among Height, Penile Length, and Foot SizeAnnals of Sex Research. 1993;6(3):231-235. doi:10.1177/107906329300600305

  7. Kadono Y et al. Changes in penile length after radical prostatectomy: Investigation of the underlying anatomical mechanism. BJU Int. 2017 Aug;120(2):293-299. doi:10.1111/bju.13777

  8. Kwon YS et al. Longitudinal recovery patterns of penile length and the underexplored benefit of long-term phosphodiesterase-5 inhibitor use after radical prostatectomy. BMC Urol. 2018 May 9;18(1):37. doi:10.1186/s12894-018-0341-8

  9. National Cancer Institute. Penis.

  10. Prause N, Park J, Leung S, Miller G. Women’s preferences for penis size: a new research method using selection among 3d modelsPLoS One. 2015;10(9):e0133079. doi: 10.1371/journal.pone.0133079

  11. Eisenman R. Penis size: Survey of female perceptions of sexual satisfaction. BMC Womens Health. 2001;1:1. doi: 10.1186/1472-6874-1-1

  12. Wylie KR, Eardley I. Penile size and the 'small penis syndrome'. BJU Int. 2007 Jun;99(6):1449-55. doi: 10.1111/j.1464-410X.2007.06806.x.

  13. Cleveland Clinic. Micropenis. 2018.

  14. Althof SE, Cappelleri JC, Shpilsky A, et al. Treatment responsiveness of the Self-Esteem And Relationship questionnaire in erectile dysfunction. Urology. 2003;61(5):888-892. doi: 10.1016/s0090-4295(03)00041-4

  15. Lawrance K-A, Byers ES. Sexual satisfaction in long-term heterosexual relationships: The interpersonal exchange model of sexual satisfactionPersonal Relationships. 1995;2(4):267-285. doi: 10.1037/fam0000205. Epub 2016 Apr 14

  16. Yafi FA, Alzweri L, McCaslin IR, et al. Grower or shower ? Predictors of change in penile length from the flaccid to erect state. International Journal of Impotence Research. 2018;30(6):287-291.

  17. University of Indiana Kinsey Institute. Penis size faq and bibliography.

  18. Gallo CBM, Costa WS, Furriel A, Bastos AL, Sampaio FJB. Modifications of erectile tissue components in the penis during the fetal period. PLoS One. 2014;9(8).

  19. Grov C, Parsons JT, Bimbi DS. The association between penis size and sexual health among men who have sex with men. Arch Sex Behav. 2010 Jun;39(3):788-97. doi: 10.1007/s10508-008-9439-5

  20. Young Men’s Health. When will my penis stop growing in size? Updated 2021.

  21. Urology Care Foundation. What is low testosterone?

  22. Alves Barboza R, da Silva EA, Ruellas T, Damião R. Anthropometric study of penile length in self-declared Brazilians regarding the color of the skin as White or Black: the study of a mythInt J Impot Res. 2018;30(1):43-47. doi:10.1038/s41443-017-0009-z