Vertical Jump Calculator

A vertical jump calculator that measures the jump three ways. Enter a hang time and it applies h = g t squared divided by 8; enter a standing reach and the highest point touched and it takes the difference; enter a jump height and a body mass and it returns the Sayers peak power and Lewis average power estimates. Hang time is the least reliable of the three, because ankle extension at takeoff and landing inflates it. The power formulas are published regressions rather than physics, so they drift badly outside the range they were fitted on.