Where is defense in character stats?

It would be nice to know what that equation is. As it is, I find it hard to know the value of a defense mod or bonus.

Defense refers to armor and resistance collectively.

The percentage for armor is not additive. As Kyno mentioned, you can google calculators that will solve it for you. But basically, the percentage that is displayed in the stats is the amount of damage that will be mitigated (not taking into account opponent's defense penetration). There is an invisible defense flat stat that is used to calculate this percentage based on level. When a mod (or in game status effect) says it adds +25% defense, it adds 25% of that flat stat. This does NOT translate to an increase of 25% damage mitigation, which is why the stat says only +7.5% from mods.

There is an equation to calculate one from the other.

I forget the actual details, we either used to be able to see it in game, or maybe it was listed on SWGOH, either way that direct stat was hidden and now we can only calculate that value.

Physical Defense% = Armor / {Armor + (Level*7.5)}
Special Defense% = Resistance / {Resistance + (Level*7.5)}

My understanding is that level is the attacking character's level. For the purposes of showing a percentage on your character stats page, it computes %defense using your character level, but in an actual battle it uses the attacking character's level.

Example assuming everyone at Level 85:
Character's armor is 500, so their physical defense is 43.96%
Add a 20% defense mod and their armor goes up to 600, increasing their physical defense to 48.48%
Attacker has 200 Armor Penetration, armor reduced to 400, decreasing physical defense to 38.55%

And this is why they will eventually increase the level cap, and when they do, lsgtb will become playable. Once the level difference gap is closed, the damage mitigation will go to normal levels.

Defense = (Armor*(CharacterLevel*7.5))/100-Armor)

Armor = (Defense*100)/(Defense+(CharacterLevel*7.5))

This is the accurate answer. Unfortunately only way to know is math lol

https://gaming-fans.com/2017/12/swgoh-advanced-armor-function-defense/