Unfortunately for some men, the concern about the size of their penis can cause significant worry and stress however nearly all men are "normal" in size.
Less than 1% of men had a flaccid penis longer than 11 cm (4.3 inches). On the flip side, less than 2% of men had a flaccid penis less than 7cm (2.8 inches) in length.[i] However, flaccid lengths can change by an inch or more depending on temperature and physical activity. However, it should be noted that the size of the flaccid penis compared to the size of the erect penis are not always correlated. For example, a man may be slightly above average when flaccid then slightly below average when erect. Research has suggested that men who are smaller when flaccid actually “grow” more when they get an erection, so that in the end, nearly all men have an erect penis that is about the same size – no matter how big or small they are when flaccid. This supports the saying that “some men are ‘show-ers’ and some men are ‘growers’.”[ii]
Since most men concerned with penis size are often referring to the size of the erect penis, erect sizes are discussed in detail in the section on erections. Click on one of the following to learn more about erect penis size:
[ii] https://www.ncbi.nlm.nih.gov/pubmed/22375645 (12/10/16)