SITE UNDER CONSTRUCTION!!!
I accidently overwrote the current version with an older version when upgrading it.
This site will let you know what your exp upgrades will be at each upgrade level, how much exp you gain each hour, day, and how much of a level you get each day at your current level. :)
~Cheers, DarkArchon.
Note: Calculations are still not accurate for levels below 150.
Other resources
Find the stats you need to effectively kill monsters or other players.
Calculate group stats with just your stats and 3 mercenaries.
Brief explaination of my hell forge suggestion, which got added, and a calculator to show the bonuses an item would get with this system.