I think I've come across the most accurate and correct one available. Most of the previously mentioned ones relied on self measurements, or a small sample. I found an article on ABC News.com about a recent study conducted.
Now, I trust this study more than most, because it has a motivation well beyond any other: Money.
The study was conducted by the Lifestyles Condom Company, in an effort to ensure proper fit of their condoms. They also used somewhat more demanding standards of measurement than previous studies.
For example, the popular Kinsey study done in the mid'1940's involved self measurement recorded on a postcard. This one involved a doctor and registered nurses, and all measurements were taken twice, by different nurses, to ensure they were valid.
So, since I'm sure you're all impatient and wonders just what the actual average is, here's the figures, according to the survey:
- About two thirds of men range between 5.1 inches and 6.2 inches.
- About three fourths of men fall under the Kinsey reported average of 6.2 inches.
- The average male penis is 5.877 inches long
There we have it, I suppose. Make of it what you will. ;-)