PSO2: How much ATKPWR is 1%?

I see this asked very often. In many cases it is more accurate to simply look at your own stats instead of trusting some magic numbers and glossing over how things work.
Might as well try to make this convenient for everyone.

Calculate

Effective ATKPWR

Explanation

Base ATKPWR

The ATKPWR value shown in the character status window with no weapon, units, or rings equipped.
Note that if ATK Up SSAsPWR Up SGAs are used on units, they should be included here instead as they are affected by buffs.

Units & Rings ATKPWR

ATKPWR from units and rings including affixesaugments but excluding SSAsSGAs.

Weapon Base ATKPWR

ATKPWR of the weapon used excluding affixesaugments.
Bonus stats gained from using an extended weapon with Bouncer's Craft Mastery should be excluded.

Weapon Affix ATKAugment PWR

ATKPWR from affixesaugments on the weapon.
Bonus stats gained from using an extended weapon with Bouncer's Craft Mastery should be included here instead.

Buffs %

Percentage increase from ATKPWR buffs. This applies to base ATKPWR only.

Enemy DEF

This value is not visible but can be measured by experiments. Most enemies at the same level have the same DEF value. There are exceptions with their DEF values scaled up or down from the level reference. For an example case which everyone loves, Lv.20 VR Training Rockbear has 100 DEF.

Enemy Element Weak %

This is the weakness multiplier if the enemy is weak to weapon element. Set to 0% if neutral.
Most enemies have 20% element weakness. There are many special cases deviating from the norm, however.
This has no effect on techs for our purpose. Accounting for element weakness does not really matter for techs in this calculation as it is just another multiplier applied to the final damage.

Attack type

This distinction has to be made because techs do not use attribute value of the weapon at all, thus weapon element damage is zero. On the other hand, Photon Arts and other non-tech attacks will deal full damage in their original damage types, plus another 60% (assuming 60 attribute) of weapon base ATKPWR as elemental.

Summoner

Summoners are weird. Values used in the calculation are slightly different so adjustments have to be made. Some of these might not be 100% verified but they should be mostly accurate.

• Base ATKPWR includes:
  • Player ATKPWR value without weapon equipped. This also includes units, unit affixesaugments, and rings.
  • Pet BonusPlus Stats (the extra stats gained by feeding pets).
  • Conditional stats gained from candiessweets (Support Roll).
• Units & Rings ATKPWR: 0. Yes, zero.
• Weapon Base ATKPWR: Pet's base stats excluding Pet BonusPlus Stats.
• Weapon Affix ATKAugment PWR: Flat stats gained from candiessweets (Cookies).

Luster

Luster adds yet another exception to the calculation, making this attempt at simplifying things more complicated for some reason. With Non-element, 70% of weapon base ATKPWR is added in exchange for removing weapon element damage entirely. This can be simulated in a few ways, though for now I will just recommend one:

• Add 70% of weapon base ATKPWR to Weapon Affix ATKAugment PWR (including decimal digits).
• Switch attack type to tech. This removes weapon element damage from the calculation.

Compromises

There are some assumptions and compromises made to remove some of the complexity involved.

• The formula used is just a part of the damage formula, thus the effective ATKPWR value shown is not representative of the actual damage done as it needs to go through another set of multipliers from skills, potentials, and many other stuff. The results are simply good estimates for how much ATKPWR is needed to improve overall damage by a certain percentage.
• Part damage multiplier is assumed to be 1 which is the most generic situation. This value changes against enemies with weaknesses/resistances against specific damage types. A common example is the headshot multiplier. This affects the ratio between weapon damage (affected by this multiplier) and weapon element damage (affected by element weak % instead).
  I could totally add this as another input field, but I felt like it would be a pain to explain what it is.
• Weapon attribute value is assumed to be 60. Other values are not really relevant enough to be worth considering.
• There is no damage variance. The resulting value is the maximum possible, AKA a critical hit.

Acknowledgements

I would like to thank everyone who keeps asking the same question over and over.