you kinda got it right, stand with your feet straight touching the wall and put your arm straight up.. mark a line or tag wherever your arm is on the wall. now from the spot your in jump straight up and mark another tag as high as you can.. you should do this 3 times a day and each time you jump do it 3 times and work out the average for it, thats the way i got told to measure my vert

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Height:6'2
Standing Vertical Jump: 32.5"
Running Vetical Jump: 36.8"

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