What is the average penis size worldwide? A 2020 analysis of research on penis size found that the average length of an erect penis across the globe is between 5.1 and 5.5 inches. Researchers believe that due to volunteer measurement bias, the actual average penis size is likely closer to the lower range. This infographic explores the average size of erect and flaccid penises across the globe both in length and in circumference. Sudan ranks first for the longest average erect penis length at 7.07 inches or 17.95 centimeters. To put that into perspective, a butter knife is about 7 inches long. In last place is Thailand with an average erect penis length of 3.71 inches or 9.43 centimeters. France ranks first for both flaccid penis thickness (4.29 inches/10.90 centimeters) and erect penis thickness (5.37 inches or 13.63 centimeters). Africa has the greatest flaccid length overall at 3.97 inches (10.08 centimeters) and South America has the greatest erect length overall at 6.05 inches (15.36 centimeters)
