No other part of the body makes guys as insecure as their penis. Most want to know where they stand in the size stakes. That’s why I’ll give you some figures.
You measure the length of the erect penis when you are at a maximum state of arousal. Measure on top, from your pubic bone to the tip of the glans.
Erect penises of adults are normally anywhere between 4,7 and 7 inch (12-18 cm.), with an average of 5,9 inch (15 cm).
The smallest are the micro-penises, which are about 2 inches long.
There are penises that are erect more than 7,8 inch (20 cm), but these are exceptional. Only 1 in 10.000 man has a penis of 9,8 inch (25 cm).
Many guys think their penis is too small, even when they are average or bigger than average. Research has shown that many guys want theirs three inch longer. But for sex this would be a disaster!

Know what’s up
Average penis size from early till late teens

Do girls find penis size important?