To calculate armor class in 5e, add your Dexterity modifier to your armor’s AC, unless you’re wearing heavy armor. Here’s how to calculate your armor class depending on which armor you’re wearing:
|Armor||Armor Class (AC)||Stealth|
|Unarmored||10 + Dex modifier|
|Padded||11 + Dex modifier||Disadvantage|
|Leather||11 + Dex modifier|
|Studded leather||12 + Dex modifier|
|Hide||12 + Dex modifier (max 2)|
|Chain shirt||13 + Dex modifier (max 2)|
|Scale mail||14 + Dex modifier (max 2)||Disadvantage|
|Breatplate||14 + Dex modifier (max 2)|
|Half plate||15 + Dex modifier (max 2)||Disadvantage|
*Requires 13 Strength to wear
**Requires 15 Strength to wear
Player’s Handbook pg. 145
If you’re wearing anything except heavy armor, you add your Dexterity modifier to calculate your AC — or subtract your Dexterity modifier, if it’s negative. You don’t suffer from a negative Dexterity modifier in heavy armor.
To calculate your armor class without armor, simply add 10 to your Dexterity modifier (Player’s Handbook, pg. 14).
Some armor types give disadvantage on Stealth checks, because they are noisy to wear. If you make a Stealth check while wearing any of those types of armor, you roll 2d20 and use the lower number as your result.
Other Ways to Calculate Armor Class in 5e
Two classes in DnD 5e have Unarmored Defense as a feature — the Barbarian and Monk.
Barbarian Unarmored Defense. While a Barbarian is wearing no armor, they calculate AC as 10 + Dexterity modifier + Constitution modifier.
Monk Unarmored Defense. While a Monk is wearing no armor or shield, they calculate AC as 10 + Dexterity modifier + Wisdom modifier.
Other Ways to Increase Armor Class in 5e
Defense Fighting Style. +1 AC while wearing armor. Available to Fighters, Paladins, Rangers, and anyone with martial weapon proficiency who takes the Fighting Initiate feat (TCoE 80).
Magic Items. Magic armor can grant +1, +2, or +3 AC, depending on its rarity, in addition to its normal armor value. Other, non-armor magic items in the game can also increase AC, but they are rare.
The Mage Armor spell. This changes the AC calculation for an unarmored creature to 13 + Dexterity modifier (instead of 10). This does not stack with the Barbarian or Monk Unarmored Defense features.
Cover. If a creature is behind cover, they have bonus AC. If they have half cover (about half of their body is blocked by something), they have +2 AC. If they have three-quarters cover, they have +5 AC.
Armor Class FAQ
How do I maximize my AC in 5e? You maximize your AC in 5e by wearing a shield, increasing your Dexterity modifier to 20 if you want to wear light armor, increasing your Dexterity modifier to 14 if you want to wear medium armor, or increasing your Strength ability score to 15 if you want to wear heavy armor.
Additionally, you should upgrade your armor to the best available for light (Studded Leather), medium (Half Plate), or heavy (Plate) armor. You’ll also need the defense fighting style and magic armor that provides bonus AC.
What is the best armor in DnD 5e? The best armor in DnD 5e is plate armor, by base AC value. It provides 18 AC and is wearable by any character who has 15+ Strength and is proficient in heavy armor.
It costs 1,500 gold, and you’ll have disadvantage on Stealth checks while wearing it, but plate armor is the most defensively sound armor in DnD 5e.
What happens if you don’t have armor proficiency? “If you wear armor that you lack proficiency with, you have disadvantage on any ability check, saving throw, or attack roll that involves Strength or Dexterity, and you can’t cast spells” (PHB 144). Basically, your character can wear any armor, but if they’re not proficient with it, your character becomes severely gimped.
Do AC calculations stack? No, AC calculations do not stack. For example, if you are an unarmored Monk with Mage Armor active, you either half 10 + Dexterity mod + Wisdom mod as your AC, or you have 13 + Dexterity mod as your AC.