Truth is, the owner of a penis seems to care much more about its size than anyone else. The guy who looks bigger than you is probably worried that he's not as big as the guy in the next shower stall, who's probably worried that he's got too much acne, or that he's too short. Puberty can be rough going. However, if this matters a lot to you, you can take comfort in the following:
Differences in penis length are exaggerated in the non-erect state--these differences tend to even out during erection.
At your age, you likely have a good deal more growing to do-- everywhere.
Penis length has little to do with sexual function.
I know, I know--get to the point. To answer your question, the average ADULT male's penis is about 4 inches long when flaccid, and a little over 6 inches long when erect (measured along the top).
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