40 mph pitch in little league is equivalent to what on MLB?

Answer 1

If the measure of ease of hitting a fastball were how long the batter sees it, then the calculation would be straightforward. Dividing the major league distance to the mound, 60.5 ft, by the little league distance, 46 ft, gives approximately 1.3152. Multiplying 40 mph by 1.3152 gives 52.6 mph, which a major league batter should easily hit. Multiplying 50 mph by 1.3152 gives 65.76 mph, which a major league batter should also easily hit if it is a fastball. A 90 mph fastball, which is somewhat challenging to a major league batter, would be equivalent to 90 mph divided by 1.3152 = a 68.43 mph fastball in little league, which is not expected. Since one mile is 5280 ft and one hour is 3600 seconds, a speed in miles per hour can be converted to feet per second by multiplying by 5280 ft / 3600 sec = 1.467 ft/sec = 1 mph. So the 40 mph little league pitch and the 52.6 mph major league pitch each give the batter a 46 ft / 58.67 ft/sec = 0.784 sec look. The 50 mph little league pitch (if there is one) and the 65.76 mph major league pitch each give the batter a 46 ft / 73.35 ft/sec = 0.627 sec look. The 90 mph major league fastball gives the batter a 60.5 ft / 118.36 ft/sec = 0.511 sec look. However, even this interval is much longer than the typical 0.1 sec human reaction time. Perhaps a batter needs about half a second to swing. It is possible though difficult to hit a curve ball or sinker. The measure of difficulty for that might be the distance the ball travels in the last 0.5 sec, and that doesn’t depend on the distance to the mound if the speed is measured near the plate. It just depends on the speed, which is easier to achieve if the mound is near the plate, and on the curve radius. So converting pitch speed by length of look probably over-corrects, especially if the fastball has some spin. Perhaps the mean of actual and converted speeds would be a better estimate of major league equivalents for little league pitches.

Answer 2

75mph is 75mph anywhere. You might want to reword that question.

Answer 3

about 83 to 85 mph