This is a guide I have created for myself to judge the value of tanking items and which to use to build the best balance between threat AND mitigation. This guide does not take into account, chance on hit items such as HoJ or Deathbringer Proc as these are pure TPS items which are situation for lower content. That being said, you should aim to keep above 400 DEF with your TPS items on.
I have broken down stats to = Tank Points (TP)
1 Stam = 1.5 TP
1 Agil = 1.5 TP
1 Block = 2 TP
1 Block Val = 0.33TP
1 Hit = 18 TP
1 Crit = 9 TP
1 Dodge = 10 TP
1 Parry = 12.5 TP
1 DEF = 4 TP
50 Armor = 1 TP
1 Str = 0.225 TP
1 AP = 0.1 TP
1 DPS = 3.5 TP
1 Skill = 2 TP
1H Weapon Enchant (15 Agil/Crusader) = 22.5 TP
(Ideally you have a top Avoidance/Mitigation weapon with 15 Agi and a TPS weapon with Crusader)
**Note - Adjust Base DEF/Stam to the need of each fight's mechanics**
Using the key above, we can break down the value of individual items. I have broken down a list of the most sought after and controversial items per slot to obtain a better understanding of how those items perform in terms of overall tanking (Effective Health Pool / Avoidance / Mitigation / Threat)
Tank Weapons:
Bloodlord's Defender + Enchant (48.2 DPS)
http://db.vanillagaming.org/?item=19867
15 Stam + 80 Armor + 4 Def + Enchant + 48.2 DPS = 231.3 TP (+10 if Human)
Claw of the Black Drake + Enchant (56.3 DPS)
http://db.vanillagaming.org/?item=19365
13 Str + 7 Stam + 1 Crit + Enchant + 56.3 DPS = 234.975 TP
Doom's Edge + Enchant
http://db.vanillagaming.org/?item=19362
16 Agil + Enchant + 9 Str + 7 Stam + 51.5 DPS = 239.27 TP (+10 if Orc)
Sickle of Unyielding Strength + Enchant (51.4 DPS)
http://db.vanillagaming.org/?item=21392
15 Str + Enchant + 6 Agil + 9 Stam + 4 Def + 51.4 DPS = 244.275 TP (+10 if Orc)
Spineshatter + Enchant (52.5 DPS)
http://db.vanillagaming.org/?item=19335
16 Stam + Enchant + 5 Def + 9 STR + 52.5 DPS = 258.925 TP (+10 if Human)
Crul'shorukh, Edge of Chaos + Enchant (62.8 DPS)
http://db.vanillagaming.org/?item=19363
13 Stam + Enchant + 36 AP + 62.8 DPS = 265.4 TP (+10 if Orc)
Blessed Qiraji Pugio + Enchant (60.6 DPS)
http://db.vanillagaming.org/?item=21244
7 Stam + Enchant + 1 Hit + 1 Crit + 18 AP + 60.6 DPS = 273.9
Quel'Serrar w/ proc (100% uptime) +Enchant (52.5 DPS)
http://db.vanillagaming.org/?item=18348
12 Stam + Enchant + 300 Armor + 13 Def + 52.5 DPS = 282.25 TP (+10 if Human)
Blessed Qiraji War Hammer + (60.7 DPS)
http://db.vanillagaming.org/?item=21268
12 Stam + Enchant + 10 Str + 8 DEF +70 Armor + 60.7 DPS = 288.6 TP (+10 if Human)
Tank Shields:
Draconian Deflector
http://db.vanillagaming.org/?item=12602
2153 AC + 40 Block Value + 10 Def + 7 Stam = 106.76 TP
Aegis of the Blood God
http://db.vanillagaming.org/?item=19862
2575 AC + 77 Block Value + 7 Def + 2% Block = 108.91 TP
Buru's Skull Fragment
http://db.vanillagaming.org/?item=21485
2575 AC + 47 Block Value + 6 Def + 20 Stam + 11 Str = 123.485 TP
Earthen Guard
http://db.vanillagaming.org/?item=20688
2468 AC + 56 Block Value + 7 Def + 19 Stam = 124.34 TP
Elementium Reinforced Bulwark
http://db.vanillagaming.org/?item=19349
2893 AC + 73 Block Value + 7 Def + 23 Stam = 144.45 TP
Blessed Qiraji Bulwark
http://db.vanillagaming.org/?item=21269
2964 AC + 70 Block Value + 8 Def + 20 Stam + 3% Block = 150.38 TP
Cloaks:
Overlord's Embrace
http://db.vanillagaming.org/?item=19760
140 AC + 10 Stam + 7 Def + 1% Block = 47.8 TP
Drape of Unyielding Strength
http://db.vanillagaming.org/?item=21394
52 AC + 15 Str + 9 Agil + 9 Stam + 1 Hit = 49.415 TP
Redoubt Cloak
http://db.vanillagaming.org/?item=18495
45 AC + 15 Stam + 7 Def = 51.4 TP
Sandstorm Cloak
http://db.vanillagaming.org/?item=21456
135 AC + 12 Stam + 12 Str + 1 Dodge + 6 Def = 55.15 TP
Cloak of Concentrated Hatred
http://db.vanillagaming.org/?item=21701
56 AC + 16 Agil + 11 Str + 15 Stam + 1 hit = 68.095 TP
Cloak of the Golden Hive
http://db.vanillagaming.org/?item=21621
59 AC + 19 Stam + 13 Str + 10 Agil + 6 Def = 71.605 TP
Trinkets:
Zandalarian Hero Badge
http://db.vanillagaming.org/?item=19948
Up-time of 16.66%: 8 hits taken single target in 20 seconds.
2,000 Armor + 30 Def = 160 TP, - 16 TP per hit taken. 8th taken = 48 TP. Take the average TP of the up-time = 104.
Multiply this by the 16.66% up-time = 17.326 TP.
*Note*
If you are tanking an add that is killed within the first 47 seconds (43% up-time) of a fight, this trinket has a TP value of 44.73, making it better than Onyxia Blood Talisman for the duration of the fight.
If you are tanking an add that is killed within the first 30 seconds (68% up-time) of a fight, this trinket has a TP value of 70.72, making it better than Styleen's Impeding Scarab for the duration of the fight.
Lifegiving Gem
http://db.vanillagaming.org/?item=19341
Up-time is 6.66%.
Taking a buffed tank HP of 8k (non world buffed), gives 120 Stam (180 TP) and heals for 1,200 (22.5 TP) of the duration of the trinket up-time = 202.5 TP
Factoring in up-time of 6.66% this trinket = 13.365 TP
*Note*
If you are tanking an add that is killed within the first 90 seconds (22% up-time) of a fight, this trinket has a TP value of 44.55, making it better than Onyxia Blood Talisman for the duration of the fight.
If you are tanking an add that is killed within the first 57 seconds (35% up-time) of a fight, this trinket has a TP value of 70.72, making it better than Styleen's Impeding Scarab for the duration of the fight.
Onyxia Blood Talisman
http://db.vanillagaming.org/?item=18406
1 Parry + 8 Def = 44.5 TP
Drake Fang Talisman
http://db.vanillagaming.org/?item=19406
56 AP + 2 Hit + 1 Dodge = 51.6 TP
Styleen's Impeding Scarab
http://db.vanillagaming.org/?item=19431
5% Block + 24 Block Value + 13 Def = 69.92 TP
Rings:
Master Dragonslayer's Ring
http://db.vanillagaming.org/?item=19384
14 Stam + 48 AP + 1 Hit = 43.8 TP
Don Julio's Band
http://db.vanillagaming.org/?item=19325
11 Stam + 1 Crit + 1 Hit + 16 AP = 45.1 TP
Band of Jin
http://db.vanillagaming.org/?item=19925
14 Agil + 8 Stam + 1 Hit = 51 TP
Heavy Dark Iron Ring
http://db.vanillagaming.org/?item=18879
110 AC + 20 Stam + 5 Def = 52.2 TP
Overlord's Crimson Band
http://db.vanillagaming.org/?item=19873
9 Str + 10 Stam + 8 Agil + 7 Def = 57.025 TP
Angelista's Touch
http://db.vanillagaming.org/?item=21695
17 Stam + 11 Str + 1 Dodge + 6 Def = 61.975
Archimtiro's Ring of Reckoning
http://db.vanillagaming.org/?item=19376
28 Stam + 14 Agil = 63 TP
Signet Ring of the Bronze Dragonflight
http://db.vanillagaming.org/?item=21200
24 Stam + 13 Str + 7 Def = 66.925 TP
Signet Ring of the Bronze Dragonflight
http://db.vanillagaming.org/?item=21205
24 Agil + 13 Stam + 1 Hit = 73.5 TP
Band of Accuria
http://db.vanillagaming.org/?item=17063
10 Stam + 16 Agil + 2 Hit = 75 TP
Ring of Emperor Vek'lor
http://db.vanillagaming.org/?item=21601
100 AC + 18 Stam + 12 Agil + 9 Def = 83 TP
Ranged Weapons:
Huhuran's Stinger
http://db.vanillagaming.org/?item=21616
18 Agil = 27 TP
Mandokir's Sting
http://db.vanillagaming.org/?item=20038
11 Agil + 8 Stam = 28.5 TP
Dragonbreath Hand Cannon
http://db.vanillagaming.org/?item=19368
14 Agil + 7 Stam = 31.5
Crossbow of Imminent Doom
http://db.vanillagaming.org/?item=21459
7 Agil + 5 Stam + 5 Str + 1 Hit = 37.125 TP
Amulets:
Pendant of the Shifting Sands
http://db.vanillagaming.org/?item=21506
21 Stam + 14 Str + 4 Def = 46.65 TP
Talisman of Protection
http://db.vanillagaming.org/?item=19871
8 Stam + 9 Def + 1 Dodge = 58 TP
Rage of Mugamba
http://db.vanillagaming.org/?item=19577
8 Agil + 8 Str + 13 Stam + 6 Def + 2% Block = 61.3 TP
Medallion of Steadfast Might
http://db.vanillagaming.org/?item=17065
13 Stam + 9 Str + 1 Dodge + 8 Def = 63.525
Pendant of the Qiraji Guardian
http://db.vanillagaming.org/?item=21700
17 Stam + 12 Str + 11 Agil + 6 Def = 68.7 TP
Master Dragonslayer's Medallion
http://db.vanillagaming.org/?item=19383
14 Agil + 24 Stam + 7 Def = 85 TP
Mark of C'Thun
http://db.vanillagaming.org/?item=22732
24 Stam + 10 Def + 1 Dodge + 1 Hit = 104 TP
Head Slot
Helm of Might
http://db.vanillagaming.org/?item=16866
608 AC + 35 Stam + 15 Str + 1 Dodge + 7 Def = 106.035 TP
Helm of Domination
http://db.vanillagaming.org/?item=21460
661 AC + 28 Stam + 21 Str + 11 Agil + 1 Parry + 7 Def = 116.945 TP
Helm of Wrath
http://db.vanillagaming.org/?item=16963
696 AC + 40 Stam + 17 Str + 11 Def = 121.745 TP
Conqueror's Crown
http://db.vanillagaming.org/?item=21329
739 AC + 18 Agil + 29 Str + 34 Stam + 6 Def = 123.305 TP
Shoulder Slot
Darksoul Shoulders
http://db.vanillagaming.org/?item=19695
507 AC + 24 Stam + 1 Hit = 64.14 TP (87.47 TP if set bonus obtained)
Pauldrons of Might
http://db.vanillagaming.org/?item=16868
562 AC + 22 Stam + 15 Str + 2% Block + 5 Def = 71.615 TP
Stockade Pauldrons
http://db.vanillagaming.org/?item=14552
472 AC + 20 Stam + 10 Def = 79.44 TP
Drake Talon Pauldrons
http://db.vanillagaming.org/?item=19394
634 AC + 20 Agil + 20 Str + 17 Stam + 1 Dodge = 82.68 TP
Field Marshal's Plate Shoulderguards
http://db.vanillagaming.org/?item=16480
626 AC + 23 Stam + 18 Str + 16 Agil + 1 Hit = 93.07 TP
Pauldrons of Wrath
http://db.vanillagaming.org/?item=16961
642 AC + 27 Stam + 13 Str + 27 Block Value + 7 Def = 93.175 TP
Paulderons of the Unrelenting
http://db.vanillagaming.org/?item=21639
650 AC + 30 Stam + 11 Str + 9 Def + 1 Dodge = 106.475 TP
Conqueror's Spaulders
http://db.vanillagaming.org/?item=21330
659 AC + 16 Agil + 20 Str + 21 Stam + 4 Def + 1 hit = 107.18 TP
Chest Slot
Darksoul Breastplate
http://db.vanillagaming.org/?item=19693
736 AC + 32 Stam + 1 Hit = 80.72 TP (104.053 TP if set bonus obtained)
Breastplate of Might
http://db.vanillagaming.org/?item=16865
749 AC + 28 Stam + 20 Str + 3% Block + 7 Def = 95.48 TP
Zandalar Vindicator's Breastplate
http://db.vanillagaming.org/?item=19822
828 AC + 23 Str + 24 Stam + 15 Agil + 4 Def = 96.235 TP
Deathbone Chestplate
http://db.vanillagaming.org/?item=14624
637 AC + 12 Stam + 17 Def = 100.74 TP
Breastplate of Wrath
http://db.vanillagaming.org/?item=16966
857 AC + 40 Stam + 17 Str + 11 Def = 124.965 TP
Conqueror's Breastplate
http://db.vanillagaming.org/?item=21331
985 AC + 24 Agil + 34 Str + 38 Stam + 6 Def = 144.35 TP
Bracer Slot
Bracers of Might
http://db.vanillagaming.org/?item=16861
328 AC + 23 Stam + 11 Str = 43.535 TP
Zandalar Vindicator's Armguards
http://db.vanillagaming.org/?item=19824
304 AC + 13 Str + 13 Stam + 13 Agil = 48.005 TP
Bracers of Heroism
http://db.vanillagaming.org/?item=21996
296 AC + 14 Stam + 9 Str + 5 Agil + 3 Def = 48.445 TP
Bracelets of Wrath
http://db.vanillagaming.org/?item=16959
375 AC + 27 Stam + 13 Str = 50.425 TP
Wristguards of True Flight
http://db.vanillagaming.org/?item=18812
198 AC + 19 Agil + 11 Stam + 1 Hit = 66.96 TP
Qiraji Execution Bracers
http://db.vanillagaming.org/?item=21602
103 AC + 16 Agil +15 Str + 14 Stam + 1 hit = 68.435 TP
Hands Slot
Gauntlets of the Immovable
http://db.vanillagaming.org/?item=21479
482 AC + 18 Stam + 15 Str + 1 Parry + 5 Def = 72.515 TP
Gauntlets of Might
http://db.vanillagaming.org/?item=16863
468 AC + 17 Stam + 22 Str + 1 Hit + 5 Def = 77.81 TP
Gauntlets of Wrath
http://db.vanillagaming.org/?item=16964
535 AC + 20 Stam + 15 Str + 1 Parry + 7 Def = 84.575 TP
Gauntlets of Steadfast Determination
http://db.vanillagaming.org/?item=21674
535 AC + 20 Stam + 19 Str + 18 Agil + 9 Def = 107.975 TP
Waist Slot
Onslaught Girdle
http://db.vanillagaming.org/?item=19137
494 AC + 31 Str + 11 Stam + 1 Crit + 1 Hit = 52.255 TP
Belt of Preserved Heads
http://db.vanillagaming.org/?item=20216
108 AC + 15 Agil + 14 Str + 11 Stam + 1 Hit = 62.31 TP
Belt of Might
http://db.vanillagaming.org/?item=16864
421 AC + 15 Stam + 21 Str + 1 Dodge + 5 Def = 65.645 TP
Belt of Heroism
http://db.vanillagaming.org/?item=21994
380 AC + 15 Str + 12 Stam + 9 Agil + 7 Def = 70.475 TP
Waistband of Wrath
http://db.vanillagaming.org/?item=16960
482 AC + 20 Stam + 20 Str + 3% Block + 7 Def = 78.14 TP
Unmelting Ice Girdle
http://db.vanillagaming.org/?item=18547
452 AC + 14 Agil + 14 Str + 14 Stam + 8 Def = 86.19 TP
Ossirian's Binding
http://db.vanillagaming.org/?item=21463
258 AC + 20 Agil + 19 Stam + 1 Crit + 1 Hit = 90.66 TP
Royal Qiraji Belt
http://db.vanillagaming.org/?item=21598
512 AC + 22 Stam + 13 Str + 13 Agil + 1 Parry + 8 Def = 110.165 TP
Legs Slot
Darksoul Leggings
http://db.vanillagaming.org/?item=19694
722 AC + 22 Stam + 2 Hit = 83.44 TP (106.773 TP if set bonus obtained)
Bloodsoaked Legplates
http://db.vanillagaming.org/?item=19855
674 AC + 36 Str + 21 Stam + 10 Def = 93.08 TP
Deathbone Legguards
http://db.vanillagaming.org/?item=14623
557 AC + 20 Stam + 13 Def = 93.14 TP
Legplates of Might
http://db.vanillagaming.org/?item=16867
655 AC + 23 Stam + 24 Str + 1 Parry + 7 Def = 93.5 TP
Marshal's Plate Legguards
http://db.vanillagaming.org/?item=16479
743 AC + 28 Stam + 20 Str + 2 Crit + 1 Hit = 97.36 TP
Legplates of Wrath
http://db.vanillagaming.org/?item=16962
749 AC + 27 Stam + 19 Str + 2 Dodge + 11 Def = 123.755 TP
Conqueror's Legguards
http://db.vanillagaming.org/?item=21332
796 AC + 21 Agil + 33 Str + 24 Stam + 6 Def + 1 Hit = 132.845 TP
Feet Slot
Deathbone Sabatons
http://db.vanillagaming.org/?item=14621
438 AC + 9 Stam + 10 Def = 62.26 TP
Sabatons of Might
http://db.vanillagaming.org/?item=16862
515 AC + 26 Stam + 15 Str + 5 Def = 72.675 TP
Bloodsoaked Greaves
http://db.vanillagaming.org/?item=19913
486 AC + 25 Stam + 8 Agil + 5 Def = 79.22 TP
Marshal's Plate Boots
http://db.vanillagaming.org/?item=16483
592 AC + 24 Stam + 18 Str + 12 Agil + 1 Hit = 87.89 TP
Boots of the Fallen Hero
http://db.vanillagaming.org/?item=21688
581 AC + 20 Str + 14 Agil + 22 Stam + 1 Hit = 88.12 TP
Boots of the Unwavering Will
http://db.vanillagaming.org/?item=21706
647 AC + 29 Stam + 12 Str + 8 Agil + 5 Def = 91.14 TP
Sabatons of Wrath
http://db.vanillagaming.org/?item=16965
589 AC + 30 Stam + 13 Str + 14 Block Value + 7 Def = 92.325 TP
Conqueror's Greaves
http://db.vanillagaming.org/?item=21333
604 AC + 17 Agil +21 Str + 23 Stam + 4 Def = 92.805 TP
Chromatic Boots
http://db.vanillagaming.org/?item=19387
596 AC + 20 Agil + 20 Str + 19 Stam + 1 Hit = 92.92 TPtam + 1 Hit = 92.92 TP