Armour

This page is about the defensive stat. For equipment classified as armour, see Armour (equipment).

For the basic passive skill, see Armour (passive skill).

Armour is a form of defence that mitigates incoming physical damage from hits. Armour rating can be increased by wearing equipment, taking certain passive skills, using skills (e.g. Molten ShellMolten ShellSpell, AoE, Duration, Fire, Physical, Guard
Level: (1-20)
Cost: (8-12) Mana
Cooldown Time: 4.00 sec
Can Store 1 Use(s)
Soul Gain Prevention: 0 sec
Cast Time: Instant
Radius: 15Applies a buff that adds to your armour, and can take some of the damage from hits for you before being depleted. When the buff expires or is depleted, the skill deals reflected damage to enemies around you based on the total damage that was taken from the buff. Shares a cooldown with other Guard skills.Per 1% Quality:1Superior2Anomalous3Divergent1% increased Skill Effect DurationBuff can take additional Damage equal to 0.25% of your ArmourReflected Damage Penetrates 1% of Enemy Fire ResistanceBase duration is 3 seconds
Buff grants +(50-858) to Armour
75% of Damage from Hits is taken from the Buff before your Life or Energy Shield
Buff can take Damage equal to 20% of your Armour, up to a maximum of 10000
Reflects (100-3000)% of Damage taken from Buff as Fire Damage when Buff expires or is depleted
This Skill's Cooldown does not recover during its effectPlace into an item socket of the right colour to gain this skill. Right click to remove from a socket.), and drinking flasks (e.g. and ).

Mechanics

Along with evasion and energy shield, armour is one of the three defence types that can implicitly appear on equipment. Unlike resistance, armour has diminishing returns as its effectiveness is based on the magnitude of incoming physical damage (multiplied by 10). As a result, armour is most effective in mitigating small hits (i.e. 50% and better reduction for initial damage less than a tenth of the armour value) and least effective in mitigating very large hits (where its absolute reduction can at most be one tenth of the armour value).

Supposedly the most armour monsters have in the game is about 983.

Physical damage reduction from armour only mitigates physical damage from hits. It falls under the modifier #% additional Physical Damage Reduction when Hit. Physical Damage Reduction is capped at No results%.

Armour does not mitigate damage over time, as armour will only mitigate damage from hits. Bleed is a damage over time debuff that is based on the initial physical hit, armour would reduce the initial hit but not the damage over time. However both the initial hit and the damage over time can be mitigated with other sources for example endurance charges because they don't only apply to hits.

Armour will only mitigate physical damage hits, not for elemental or chaos damage. If the Transcendence keystone is taken, armour mitigates elemental damage hits, but not physical.

Rule of thumb

• To prevent one third of damage, you need armour 5 times the damage (e.g. 500 armour for 100 damage)
• To prevent half of damage, you need armour 10 times the damage (e.g. 1000 armour for 100 damage)
• To prevent two thirds of damage, you need armour 20 times the damage (e.g. 2000 armour for 100 damage)
• To prevent three quarters of damage, you need armour 30 times the damage (e.g. 3000 armour for 100 damage)
• To prevent 90% of damage, you need armour 90 times the damage (e.g. 9000 armour for 100 damage)
• armour will never prevent more damage than its value divided by 10 (e.g. 1000 armour will never prevent more than 100 damage)

Formulas

For a step by step calculation of formulas, see Armour/math.

The amount of physical damage reduction is a function of armour rating and the physical damage taken.

Relative Physical Damage Reduction (Base Formula)

This is the base formula all other formulas are based upon. It is used to calculate the #% additional Physical Damage Reduction when Hit factor, i.e. the percentage by which the physical damage is mitigated.

<math display="" style="background-color:transparent; padding:0;"> \color[RGB]{163,141,109} DR(A, D_{raw}) = {A \over A + 10 * D_{raw} }

   </math>

where A is the defender's armour rating and D_raw is the raw physical damage.

Required Armour Rating

To calculate the armour rating you need to mitigate a given amount of Physical Damage at specific ratio, you can use this formula:

<math display="" style="background-color:transparent; padding:0;"> \color[RGB]{163,141,109} A(D_{raw}, DR) = {DR * 10 * D_{raw} \over 1 - DR}

   </math>

Reverse Physical Damage

You can also calculate the raw physical damage that would have resulted for a given Physical Damage Reduction and Armour rating:

<math display="" style="background-color:transparent; padding:0;"> \color[RGB]{163,141,109} D_{raw}(A, DR) = {A \over 10 * DR} - {A \over 10}

   </math>

Resulting Physical Damage

To calculate the net physical damage (i.e. the damage after damage reduction, the following formula can be used:

<math display="" style="background-color:transparent; padding:0;"> \color[RGB]{163,141,109} D_{net}(A, D_{raw}) = {10 * {D_{raw} }^2 \over A + 10 * D_{raw} }

   </math>

Absolute Physical Damage Reduction

Another way of looking at it is in terms of absolute physical damage reduction:

<math display="" style="background-color:transparent; padding:0;"> \color[RGB]{163,141,109} DR_{abs}(A, D_{raw}) = {A * {D_{raw} } \over A + 10 * D_{raw} }

   </math>

Defense factor

<math display="" style="background-color:transparent; padding:0;"> \color[RGB]{163,141,109} DF(A, D_{raw}) = {A \over 10 * D_{raw} } + 1

   </math>

Examples

The plots below displays how much damage reduction occurs at different armour ratings and raw physical damage.

Armour reduction at varying armour ratings and raw physical damage

Mitigated Damage as a function of Incoming Damage and Armour Rating. Note that Rounding is usually decided in the monster's favor.

% Mitigated Damage as a function of Incoming Damage and Armour Rating

From the plot below we can further conclude:

• If raw damage is much less than Armour / 10, raw damage has a near-quadratic effect on net damage. Equivalently, in this regime raw damage has a near-linear effect on net DPS if the raw DPS is held constant.
• If raw damage is much greater than Armour / 10, raw damage has a near-linear effect on net damage. Equivalently, in this regime raw damage has little effect on net DPS if the raw DPS is held constant.
• Against attacks of a fixed raw damage, armour has a linear effect on the number of attacks it takes to deplete a certain amount of hit points.

Active skill gems

Main page: List of armour related skill gems

Related base stats

There are currently no active skill gems that have stats related to armour.

Related quality stats

There are currently no active skill gems that have quality stats related to armour.

Support skill gems

Main page: List of armour related skill gems

Related base stats

There are currently no support skill gems that have stats related to armour.

Related quality stats

There are currently no support skill gems that have quality stats related to armour.

Mechanics Scaled by Armour Rating

The following items provide some bonuses that scale with Armour rating.

Item		Stats

Related items

Flasks

Item		Duration	Usage	Capacity	Buff Effects	Stats

Unique items

See also: List of unique armours granting armour

Notable Armour Rating

Unique items that can potentially grant upwards of 1,000 Armour rating.

Item		AR

Global Armour increases

Unique items that grant increased global Armour rating.

Item		Stats	+% to global Armour Rating

Global flat Armour

Unique items that grant a flat bonus to global Armour rating.

Item		Stats	+% to global Armour Rating

Modifiers

Pure armour rating armours

No results found

Hybrid armour/evasion rating armours

No results found

Hybrid armour/energy shield armours

No results found

Hybrid armour/evasion/energy shield armours

No results found

Armour shields

No results found

Belts

No results found

Amulets

No results found

Jewels

No results found

Abyss Jewels

No results found

Corrupted

No results found

Delve

No results found

Passive skills

There are passive skills that grant armour bonuses.

Base passives

These passive skills grant increased armour rating or additional base armour rating. The Iron Reflexes keystone is special in that it converts evasion rating to armour rating. No results found for the given query.

Ascendancy passives

No results found for the given query.

Keystones

No results found for the given query.

Cluster jewel passives

The following cluster jewel-only passives are related to armour: No results found for the given query.