There is a much wider range of size in men’s penises when flaccid, with the average ranging from 1 to 4 inches. In general, smaller flaccid penises lengthen at erection by a greater percentage than do larger flaccid penises, with most men reaching an average size of 5 to 7 inches, so the flaccid size of a penis is not a good predictor of erect size. The vast majority of men measure within the average genital size range and have a penis size that is more than adequate for sexual functioning.