Attack power

Attack Power
Class	Melee Base	Ranged Base
Druid Druid	(Strength x 2) - 20	Agility - 10
Druid Druid (Bear)	(Strength x 2) + (Character Level x 3) - 20
Druid Druid (Cat)	(Strength x 2) + Agility + (Character Level x 2) - 20
Druid Druid (Moonkin)	(Strength x 2) + (Character Level x 1.5) - 20
Hunter Hunter	Strength + Agility + (Character Level x 2) - 20	(Character Level x 2) + Agility - 10
Mage Mage	Strength - 10	Agility - 10
Paladin Paladin	(Strength x 2) + (Character Level x 3) - 20	Agility - 10
Priest Priest	Strength - 10	Agility - 10
Rogue Rogue	Strength + Agility + (Character Level x 2) - 20	Character Level + Agility - 10
Shaman Shaman	Strength + Agility + (Character Level x 2) - 20	Agility- 10
Warlock Warlock	Strength - 10	Agility - 10
Warrior	(Strength x 2) + (Character Level x 3) - 20	Character Level + Agility - 10

Attack power (AP) increases your base DPS by 1 for every 14 attack power. For example, an AP of 28 will give you 2 DPS. To convert DPS into average damage per swing: (Weapon DPS + AP/14) * Weapon Speed. If dual wielding, an off-hand weapon will also receive DPS from AP with the normal damage penalty. Disregarding dual wield specialization talents, the offhand damage is then: [(Weapon DPS + AP/14) * Weapon Speed]/2.

Each point of strength increases melee attack power by 2, except for rogues, shamans and hunters who gain 1 AP per point of strength, and 1 per point of agility. Druids in cat form also gain 1 AP per point of agility. Heart of the Wild gives a druid in cat form a 10% increase in AP.

Players also receive 1 point of ranged attack power (RAP) per point of agility. Also, 1 AP = 1 Ranged Attack Power (RAP). Unless an item or effect specifically says "+__ to Melee Attack Power" or "+__ to Ranged Attack Power" then this is true. If it adds to Attack Power and does not specify "Melee" or "Ranged" then it always adds equally to both Ranged Attack Power and Melee Attack Power.

Bonuses from attack power are added to a character's DPS before attack speed bonuses come into effect. So, a character with a weapon with 10 base DPS, 2.0 attack speed, and 140 AP will have a total of 20 DPS (10 base + 140/14 from AP). If a 10% increase to attack speed is gained, DPS will increase to 22 (10% of 20 is 2) as opposed to only getting one from the base DPS, at 11, and then adding 10 from the attack power to 21.

Mob attack power

Mobs have different attack power formulas than players. Damage done per second of mobs is given by:

(Damage_from_AttackPower + Base_Weapon_Damage) * Multiplier.

For most mobs, attack power is about 30% of total damage; bosses have higher multiplier than trash mobs. That means -Attack Power debuffs have significant effect on raid mobs. Some tests suggest [Improved Demoralizing Shout] could reduce the damage taken from a level 60 mob by 25%. Thus [Curse of Recklessness] will increase the damage done of affected mob drastically. The -AP debuff is capped at -30% total damage effect, as the formula suggests.

Hunter attack power

Before patch 2.0.1, Hunters received 2 RAP per agility, whereas now they receive 1 RAP per agility. Some of this loss was made up for in AP increases from items. The reason given for this change was to keep agility from being the be-all and end-all of hunter stats, allowing for flexibility into intellect or stamina without sacrificing a large amount of AP.

After Patch 3.0.2 Hunter can gain RAP from Intellect or/and Stamina by Survival and Marksmanship Talent.

Shaman attack power

Before patch 3.0.2, Shamans received 2 AP per Strength. This was changed in 3.0.2 in preparation for Wrath of the Lich King. Shamans now receive 1 AP from strength and 1 AP from Agility. With the talent [Mental Dexterity] shamans also gain 1 AP per intellect.