Men often joke about penis size, but for some the fear of not sizing up is significant enough to seek medical attention. Most physicians have enough experience to provide basic reassurance, but a new report combines data from 20 studies to provide definitive nomograms of the flaccid, flaccid stretched, and erect penis length and girth across ages and races. 

The average length was 9.16 cm when flaccid, 13.24 cm when stretched, and 13.12 cm when erect, investigators reported in BJU International (2015; published online ahead of print). Flaccid length was correlated with erect length; despite popular belief, foot size was not predictive.