What is the formula for armor/magic resist reduction?

As far as I can tell, it's something like this:

damage reduction = armor / (armor + 100)

Is this accurate?

2 Answers

Yes, that's correct. The calculations are:

Armour Resist: Damage Reduction = Total Armor / (100 + Total Armor)

Magic Resist: Damage Reduction = Total Magic Resistance / (100 + Total Magic Resistance)

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When it comes to reduction It is indeed diminishing, but when You work out the formula for Ehp (Estimated hp) 1 point of armor actually always gives 1 additional % of hp based on the base hp.

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