Skill calculators are used to decide on a classes build without committing to it. With the heavy cost of a skill reset in game it isn't surprising that good skill calculators are some of the most sought after items. With a current level cap of 35 all skills can't even be completed to max since some require level 40. Currently Raiderwikiz has the best skill calculator since it allows you to account for the level.
The best skill calculator I found: