I recently started working on this project to implement browser based damage reduction calculator for D3.
Project is still work in progress as I just started working on it a while ago but it will be evolving rapidly when I find the time to work with it.
Tool: messor.fi/D3
Changelog: messor.fi/D3/change.log.txt
Official thread can be found on diablofans (links included as I'm unable to post urls due to low post count here :<)
You should considering adding ways to account for (some Monk specific):
Life Increase %
dodge bonuses (eg. Mantra of Evasion)
Other damage reduction increases (eg. Resolve)
Also, the Monk and Barb bonus only applies to melee damage, afaik, and at least for me in Inferno, I care more about reducing ranged damage and that from void zones and lasers. You should let ppl turn off this effect so they can see non-melee.
Also, why does this use a web service? I can't reproduce results I calculated myself, and you don't include the source code, so I can't identify the difference.
Edit: I figured out the difference - I include Dodge % in my effective health calculation, and it comes out very close without that. You should make it more clear that that isn't included.
Make your post count to 10, and copy your post here (I did read your post (if not mistaken you for other use), quite informative). Then it should be voted for sticky imho.
P.S.: We could use some more stickies in this forum part, like that one, and on Staff of Herding - there was decent thread about it, but it is lost in time now