There is a whole thread within this forum on this very subject:
http://forums.airlinepilotcentral.co...ighlight=climb


If using 3 degree gs:

10,000' to loose
divide by 318 (round up)
32 miles before fix, start descent

300 knots (ground speed) x 5 = 1500 ft/min


** vicman's formula in a previous post is incorrect