50-60
How Fast Should A 13 Year Old Pitcher Throw?
It depends on if your a girl or boy pitcher .In my opinion girls should pitch at about 50-60 average and 65 max.Boys should pitch about 55-65 average 70 max.
90mph before you are 14 minimum to get scouted.
At the age of thirteen an average pitcher should throw from around 63-68mph if you are a boy. A girl would be around 57- 64mph.