How the power level is calculated

The formula

Power = 10 × √(Attack × Defense × Healing).

Attack is the damage per second of a basic attack and your best attack spell against ordinary reference monsters. Defense is your effective health divided by 10: the health you have for 10 seconds of combat. Healing goes from ×1 to ×2 and compares how much you recover per second with that defense.

The square root joins attack and defense. Doubling only your damage raises power by 41%; doubling damage and health doubles power.

Where to see the calculation

In the character window, the Power tab shows your calculation step by step, with your numbers. On each character's public profile, open “How the power level is calculated”, below the power level: the same calculation is there, with what each item adds. With these numbers, any player can redo the calculation.

Step 1: Attack

The average hit comes from level, weapon skill and weapon attack; with a wand, from the wand's damage. It is multiplied by Damage dealt from affixes and guild, by critical and by the vocation bonus, and divided by the time between hits. The attack spell uses its average damage divided by its cooldown. Area spells and ammunition count how many enemies the area reaches, at most one box (8 monsters): Front Sweep, which only hits in front, counts 3; Great Fire Wave, with 17 tiles, counts 8. Chain spells count the targets of the chain. At the end, the sum is multiplied by time in combat: every 20 seconds of fighting, a few steps to the next monster.

Critical counts as an average. With 50% chance and +100% additional critical damage, each hit is worth 1 + 0.5 × (0.5 + 1) = ×1.75. The damage Limit only cuts the excess of very strong hits.

Step 2: Defense

Effective health is your maximum health divided by the part of the damage that gets through. The calculation uses reference hits of 400, physical and of the six elements, after armor, defense and resistances. Knights, Paladins and mages take even less damage from level 200. For Sorcerers and Druids, the mana shield adds to health.

Step 3: Healing

Recovery is regeneration, potions, healing spell and life steal per second, already discounting protection. Healing = 1 + recovery ÷ (defense + recovery). Recovering per second the same value as your defense gives ×1.5; recovering much more gets close to ×2, but never goes beyond it.

Why the top grows so fast

Everything multiplies. Refinement multiplies the attributes and lines of each item: +15 ×1.75, +16 ×2.00, +17 ×2.35, +18 ×2.80, +19 ×3.35 and +20 ×4.00. Critical grows twice, because critical chance and critical damage multiply each other: doubling both almost quadruples the bonus. Whoever takes several items to +18 with critical lines sees attack grow much faster than level.

Without affixes and refinement, characters of the same vocation and level have practically the same power. The difference at the top comes from refined equipment and the lines it carries, not from a hidden bonus: every number is in the profile's calculation.

What is not counted

The power level describes the character against ordinary monsters. Left out are damage against elites and bosses, penetration, food, mentor and rings or amulets with charges or duration. The aquarium counts: fish in active slots add their attributes, and their damage reduction joins defense. That is why the world boss, where every hit is against a boss, can have a different order than the ranking. The number also does not guarantee safety in a hunt: action bar, positioning and the monsters' elements matter.