Just saw this article referenced at DiscussFastpitch.com. The article is on a site focused on fastpitch pitching called PitchSoftball.com, and represents the observations of Gerald Warner, a pitching instructor from Colorado.

For those of you whose 14 year old daughters DON’T throw 65 mph with eight pitches (as the daughters of most people on eTeamz’s boards seem to do), don’t despair. According to the site, while the average pitch speed at a particular age varies by region, Coach Warner puts an average 14U pitch speed at 50. A 13 year old will pitch between 40 and 50, he says.

That’s pretty consistent with what I’ve seen too. There are always exceptions on both ends, but the speeds listed here are more the norms. Incidentally, an average HS pitcher is listed at 53-57 mph.

As people point out in the DiscussFastpitch post, keep in mind that speed is only one element of a successful pitcher. You need enough speed to be respectable, but you don’t have to be overpowering to be successful. Movement, location, and intelligence/pitch selection are also important – perhaps even moreso, especially at the upper levels.

Check out the article. It’s a quick read, but a good one.