Kind of inaccurate, but here it goes.

in 9th grade I measure 7.7 long and 5.25 around.

I just turned 21 a few days ago and I measure 8.5 long. Didn't get width but I assume I'm bigger now...

However, I recently tried a viagra out of curiousity and I swear I might've been 9 and so if I had to make a prediction fo me at my best I'd say

9 inches long an 5.7-6 around.