For tournament greens........ multiply the distance by .7 add or subtract elevation then add 2.
example: 12ft. putt with elevation 3in. uphill to hole, putt it to go 13.4 ft
12 x .7 = 8.4 + 3 = 11.4 +2 = 13.4 ft.
example: 12ft. putt with elevation 2in. down hill to hole. putt it to go 8.4 ft.
12 x .7 = 8.4 - 2 = 6.4 + 2 = 8.4
example: 12ft. putt with no elevation to hole, putt it to go 10.4 ft.
12 x .7 = 8.4 + 2 = 10.4 ft.
very fast greens, same calculation but multiply distance by .8