Justice Points are the currency to buy items as a reward for participating in normal and Heroic dungeons(up to level 60), "burning crusade" Normal and Heroic Dungeons(up to level 70), Wrath of the Lich King normal and heroic dungeons and raids (up to level 80),Cataclysm dungeons on normal and heroic mode (up to level 85), and Pandaren Dungeons up to level 86-87, Justice Points replaced [Emblems of Frost] and [Emblems of Triumph] --(NOTE: this was the Old World currency, now also Replaced with Justice Points) Cataclysm based raid content will reward Valor points instead,
as of Patch 5.2.0, levels 87-90 now get rewarded Valor Points instead of Justice points, If you want to buy an Justice Heirloom at that level range, your only alternative is to get valor with battlegrounds, and convert that to justice.
Justice Points are rewarded in level-appropriate dungeons and raids. while Heroic Dungeons give more Justice, you can only do an Herioc run once each day each dungeon.
Outgrowing content by out-leveling it will result in the listed objectives no longer rewarding Justice Points. Thus, for Wrath of the Lich King content, no Justice Points will be rewarded for players levels 81 and above. The same rule applies for Burning Crusade and Vanilla" content, which will also reward Justice Points.
Justice Points can be spent at a faction-specific vendor (also known as the Justice Quartermaster) or at a vendor in Dalaran for Item Level 346 rare gear, which will cost 950-2200 JP depending on the slot of the item.
There are ten "Legacy Justice Quartermaster" vendors in Dalaran and they have replaced the old Emblem vendors from Wrath of the Lich King in the Silver Enclave (Alliance) and the Sunreaver's Sanctuary (Horde).
The Alliance vendor, Magatha Silverton, is located in Stormwind in the Command Center, in the southernmost part of Old Town. She is standing beside Faldren Tillsdale, the Valorous Quartermaster.
The Horde vendor, Gunra, is located in Orgrimmar on the roof of Grommash Hold, in the center of the Valley of Strength. She is standing beside Jamus'Vaz, the Valor Quartermaster.
Slot
Justice Points
Chest
2200
Hands
1650
Legs
2200
Head
2200
Off-Hand
950
Necklace
1250
Shoulder
1650
Waist
1650
Conversion of Emblems to Justice Points
When players first log in after Patch 4.0.1, the number of Justice Points they have would be calculated as follows:
JP = 11.58 * (EoT + EoF)
where:
JP = the number of Justice Points;
EoT = the number of Emblems of Triumph;
EoF = the number of Emblems of Frost.
Players cannot stockpile more than 4,000 Justice Points at any time by normal means of running instances.
However, if the one-time emblem-to-point conversion grants the player more than 4,000 Justice Points, they will be unable to accumulate any additional Justice Points until they have spent the excess. Come Patch 4.0.3, any Justice Points above 4,000 will be immediately converted to gold at a ratio of 47 50 per Justice Point.
PvP-based currency will be converted to Honor points much the same way.
Other, specific currencies such as Champion's Seals will not be converted.[1]
Comparison of purchasing power
With the introduction of Justice Points (Patch 4.0.1), that replaced [Emblems of Frost] and [Emblems of Triumph], players will be able to use the same currency to purchase both Tier 9 and Tier 10, potentially skipping the earlier in favour of the latter. Obtaining Tier 10 is now in comparison faster and easier.
The conversion did affect the prices of Heirlooms as well, from using [Emblems of Heroism] to using the same currency. The prices for Heirlooms seems to be equated for the Justice Point income at level 85, which at level 80 means relatively higher costs. Example:
Any dungeon or raid which awarded these emblems will reward Justice Points instead. Anything below Emblems of Triumph, including badges from The Burning Crusade dungeon and raid content, have been converted into gold and sent to players via the in-game mail system.
Any bosses players defeat that are level-appropriate to them award Justice Points.
All items that previously cost emblems or badges of any type now cost Justice Points.