Flat Damage

Base damage is calculated depending on Path of Exile 2 Currency the skill type:

Attacks use:
Weapon damage
Unarmed base (if no weapon)
Shield damage (if shield skill)
Totem skill base (not weapon-based)

Spells used:
Damage from the Skill Gem

Added Flat Damage from gear, supports, and passives is then applied.

2.2 Damage Conversion & "Gain as Extra"

Damage can then be converted or gained as extra types:
First, conversion from you buy POE 2 Orbs skill gems (e.g., Perfect Strike)
Then, conversion from gear or passive tree

Rule of Thumb: If total conversion exceeds 100%, the proportions are normalized.

2.3 Damage Multipliers

Increased or reduced values are additive
More/Less are multiplicative

2.4 Critical Hit

If the skill crits, Critical Multiplier is applied:
Default: +100% (i.e., 200% damage)
Enemy modifiers (e.g., Battle-hardened) can reduce this multiplier.

2.5 Damage is Rolled

Now the damage is rolled between Min and Max:
Lucky/Unlucky modifiers apply here, rolling twice for the best/worst result.
Lucky and Unlucky cancel each other out if both apply.

2.6 Double/Triple Damage

Calculated after cheap Path of Exile 2 Currency roll.
Triple overrides Double if both trigger.