Velocity S=d/t

velocity/speed= distance/ Time
velocity =60.6/time
This is the real way to find how fast you throw ok.

Or you could go here:

It’s simple.

1 ft/sec = 0.681818182 mph

I’m not sure but isn’t that the average speed over the specific trajectory? Because if you see the speed meters on tv and they show Zumaya throw 100 mph this is the speed when he releases the ball, and when the catcher catches the ball the speed will be lower because of the deceleration. Or am I wrong?