dazco

I found a new fireroad today that is just plain sick ! The entire 3 or 4 miles is insanely steep, but much of it is so steep that it's all but impossible to ride up, and walking it is almost as bad. But it made me wonder, when i hear some of you cite what % a perticular grade is, how are you measuring this? Are there computers that can do this or what? I'd like to be able to know how steep some of the parts are to compare with other rides.

Thanks