There has been a lot of false information spread around the bowels of the internet lately about what the actual stat caps are for a tanking warrior at level 80. I’ve read up on TankSpot, Elitist Jerks and Something Awful (I highly recommend all of these links, by the way) to bring you the end-all-be-all of what you should be looking for as a tank in terms of your stats.
Defense for raiding: 540
Defense for heroics: 535
Hit (level 83 boss): 295 raiting
Expertise (remove dodges): 25
Expertise (remove parries): 57
If you would rather look at raiting required then these are the numbers you need:
Defense: 689 defense rating
Expertise (dodge): 205 expertise rating
Expertise (parry): ~500 expertise rating
Hit: 295 hit rating
Here’s stat conversion at level 80:
1% hit = ~32.8 hit rating
1% dodge/parry reduction = ~32.8 expertise rating
1 expertise = 8.1975 expertise rating
1 defense = 4.9 defense rating
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