How to Calculate Armor Class in 5e

An Easy Guide to Determining Armor Class in D&D 5e

Being a combat-focused tabletop roleplaying game, Dungeons & Dragons 5th Edition often involves battles between the player characters and the various monsters set before them. Knowing when an attack hits or not is crucial for running combat encounters. As such, knowing how to calculate armor class in D&D 5e is integral to understanding the game.
But, how do you figure out armor class in D&D 5e? What affects it? And, how do you increase it?
This guide breaks down how to calculate armor class in D&D 5e and features a handy calculator to help you if you need or want it.

Let’s start by going over the basic calculations for figuring out armor class in 5e.

How to Calculate Armor Class (AC) in D&D 5e

To calculate your Armor Class or AC in D&D 5e you need to know what type of armor your character uses and add the corresponding Ability Score modifier(s). Most of the time, you’ll add your Dexterity modifier with only a few exceptions when you wouldn’t.

The base number for determining a creature’s armor class in 5e is 10. This is the default number from which all AC calculations stem from. From there, you can modifier it with armor, spells, and other abilities including class features and racial traits.

Usually, you’ll add (or subtract) a creature’s Dexterity Ability Score modifier to the base number to get their armor class. So, a creature not wearing armor with a Dexterity of 12 (+1 modifier) would have an armor class of 11 (10 + 1).

That said, the most common way to figure out armor class in 5e is to figure out what type of armor a character wears. Armor usually raises the bottom most number of a character’s AC and can still usually add their Dexterity modifier to some degree.

Here’s a list breaking down how to calculate armor class in D&D 5e with armor:

  • No Armor / Unarmored AC = 10 + Dexterity modifier
  • Padded & Leather Armor AC = 11 + Dexterity modifier
  • Studded Leather AC = 12 + Dexterity modifier
  • Hide Armor AC = 12 + Dexterity modifier (up to +2, max AC 14)
  • Chain Shirt AC = 13 + Dexterity modifier (up to +2, max AC 15)
  • Scale Mail & Breastplate AC = 14 + Dexterity modifier (up to +2, max AC 16)
  • Half Plate AC = 15 + Dexterity modifier (up to +2, max AC 17)
  • Ring Mail AC = 14
  • Chain Mail AC = 16
  • Splint Armor AC = 17
  • Plate Armor AC = 18

Of course, this is just with default, mundane armor. There are a myriad of things which affect how you determine your AC in 5e.

For example, both the Barbarian and Monk classes get a feature called Unarmored Defense. This alters their unarmored AC calculations by using both Dexterity and an additional Ability Score modifier; Constitution for Barbarians and Wisdom for Monks. So, their AC calculations look like this:

  • Barbarian AC = 10 + Dexterity modifier + Constitution modifier
  • Monk AC = 10 + Dexterity modifier + Wisdom modifier

What’s more, this is only one example when armor class calculations differ greatly. Magical items, spells, feats, and other abilities can all alter how high your character’s AC is and can go.

Here’s a handy 5e armor class calculator to help you figure out your character’s AC.

How To Increase Armor Class in 5e

Metal helmet, a shield, and a battleaxe resting on the ground

You have a variety of options to increase your character’s armor class in 5e. Class choices, spells, magic items, and more can all contribute to improving your AC.

Depending on how you want to play your character, you have quite a few methods to increase your AC in 5e. More dexterous characters may want to further improve their Dexterity score while others may want to simply look at getting more protective armor.

Options for increasing your AC in 5e include:

Of course, these all come with their own nuances. So, let’s go over each of these options in greater detail starting with the most basic; increase your Dexterity.

Increase Your Dexterity Ability Score

Generally, increasing your character’s Dexterity Ability Score is a good way to improve their armor class. Most creature’s ACs use their Dexterity modifier, so increasing the modifier means improving their armor class.

All classes get the Ability Score Improvement feature at some point. Some, like Fighters, get more of them, but generally, every class gets the option to increase their Ability Scores at 4th, 8th, 12th, 16th, and 19th level. This means every class has the opportunity to increase their Dexterity Ability Score and, by extension, improve their armor class.

A creature’s Ability Score modifier increases at every even number. So, those numbers are the most important to reach if you want to improve your character’s armor class by increasing their Dexterity score.

Here’s a rundown of what the modifiers are for each Ability Score:

  • Ability Score 1: -5 modifier
  • Ability Score 2-3: -4 modifier
  • Ability Score 4-5: -3 modifier
  • Ability Score 6-7: -2 modifier
  • Ability Score 8-9: -1 modifier
  • Ability Score 10-11: 0 modifier
  • Ability Score 12-13: +1 modifier
  • Ability Score 14-15: +2 modifier
  • Ability Score 16-17: +3 modifier
  • Ability Score 18-19: +4 modifier
  • Ability Score 20: +5 modifier

So, if you have a 15 in Dexterity, you only need to add 1 more point to also improve your Dexterity modifier. However, if you have a 14, you’ll need to add at least 2 more points to increase your modifier.

Increasing your Dexterity modifier is an easy way to improve your armor class, but you need to be aware of what type of armor your character wears.

Upgrade Armor Type

Changing the type of armor your character wears can be an easy way to increase their armor class. However, you need to understand that medium and heavy armors have restrictions on adding Dexterity to their AC.

As shown above, the different levels of armor in 5e provide different amounts of base AC.

The base AC of each type of armor is as follows:

  • Light Armor
    • Padded & Light Armor: 11
    • Studded Leather: 12
  • Medium Armor
    • Hide Armor: 12
    • Chain Shirt: 13
    • Scale Mail & Breastplate: 14
    • Half Plate: 15
  • Heavy Armor
    • Ring Mail: 14
    • Chain Mail: 16
    • Scale Armor: 17
    • Plate Armor: 18

Now, the reason for the classifications (Light, Medium, & Heavy) is for easy reference on whether and how much of a character’s Dexterity modifier gets added to their armor class. The break down goes like this:

  • Light Armor: add full Dexterity modifier
  • Medium Armor: add up to 2 from Dexterity modifier
  • Heavy Armor: doesn’t add Dexterity modifier

For example, if a player character with a 16 in Dexterity (+3 modifier) wears studded leather armor (base 12 AC), their armor class equals 15 (12 + 3). But, if that same character wears hide armor (base 12 AC), their armor class would only equal 14 (12 + 2) because hide is a type of medium armor and you can’t add more than 2 for the Dexterity bonus. Likewise, if that character wears ring mail, their armor class would still only equal 14 (the base for ring mail) because you don’t add a Dexterity modifier bonus to heavy armor of which ring mail is.

Use a Shield

Shields in D&D 5e add a flat +2 bonus to the armor class of a character wielding one.

Wielding a shield gives your character a +2 bonus to their AC. Of course, you need to be wielding it, so it can’t just be sitting on your back. Your character needs to actively use their shield to gain this bonus.

Play a Character with AC Bonuses

Some racial traits and class features add bonuses to armor class.

Playing a character with a high armor class starts at character creation. Choosing a lineage with an AC boost or bonus is a good start but your class choice also can play a major role in how high you boost your character’s armor class.

These choices form the foundation for your character’s AC. So, we’ll break them down so you can see what your options are.

Racial Traits

Only 2 races give a character a bonus to their armor class; the Tortle and Warforged.

5e’s player race options don’t offer a lot in the way of improving armor class. In fact, players really only have 2 options for out-of-the-gate AC boosts from their racial pick; Tortle or Warforged. Both offer AC benefits but in different ways. Tortles increase your character’s default AC with another trait for a temporary boost while Warforged give you a flat bonus.

  • Tortle: Natural Armor and Shell Defense
  • Warforged: Integrated Protection

Class Features

Some classes give characters features which improve their armor class like the Defense Fighting Style or the Bladesinging Wizard’s Bladesong.

There are actually quite a few class features which improve or boost a character’s armor class. So, you have a variety of options when building or planning your character around having a high AC.

Here is a list of class features which increase or boost a player character’s armor class in 5e:

  • Artificer – Infusion (Enhanced Defense): +1 AC (+2 at 10th-level) when wielding the infused armor or shield
  • Barbarian – Unarmored Defense: AC = 10 + Dexterity modifier + Constitution modifier
  • Cleric (Forge Domain) – Soul of the Forge: +1 AC while wearing heavy armor
  • Druid – Wild Shape: AC becomes that of the beast or elemental you turn into
  • Fighter (Battle Master Archetype) – Maneuver (Bait and Switch): AC bonus equal to number rolled on Superiority Die
  • Fighter (Battle Master Archetype) – Maneuver (Evasive Footwork): AC bonus equal to number rolled on Superiority Die
  • Fighter, Paladin, Ranger – Fighting Style (Defense): +1 AC while wearing armor
  • Monk – Unarmored Defense: 10 + Dexterity modifier + Wisdom modifier
  • Monk (Way of the Kensei) – Path of the Kensei (Agile Parry): +2 to AC after making an unarmed strike
  • Ranger (Hunter Conclave) – Defensive Tactics (Multiattack Defense): +4 AC against a creature that has already hit you
  • Wizard (Bladesinging) – Bladesong: add Intelligence modifier to AC

Cast an Armoring Spell

There are a few spells in D&D 5e which increase a target creature’s armor class.

While armor class is typically associated with martial characters, spellcasters have a variety of AC-increasing spells either for bolstering their own defenses or helping their frontline allies. Of course, this means using a spell slot to grant these benefits, but the bonuses usually outweigh the cost.

Here is a list of armor class-increasing spells in 5e:

  • Barkskin: AC can’t be lower than 16
  • Ceremony (Wedding): +2 to AC
  • Haste: +2 to AC
  • Mage Armor: AC = 13 + Dexterity modifier
  • Polymorph / True Polymorph / Shapechange: AC becomes that of the creature you turn into
  • Shield: +5 to AC
  • Shield of Faith: +2 to AC
  • Tasha’s Otherworldly Guise: +2 to AC
  • Warding Bond: +1 to AC

Choose Armor-Based Feats

D&D 5e has a few features designed for improving armor class.

There aren’t that many feats in 5e for improving your character’s AC. In fact, there’s only 3, so you have pretty slim options. Even then, they’re not really universal options; you pretty much have to make a character with these feats in mind as they won’t work in all builds.

Here are the 3 feats in 5e which can improve your armor class:

  • Defensive Duelist: reaction to add Proficiency Bonus to AC while wielding a finesse weapon
  • Dual Wielder: +1 to AC while wielding a weapon in each hand
  • Medium Armor Master: can add +3 from Dexterity modifier to medium armor

Find Magic Armor

Many pieces of magic armor include flat bonuses to armor class. However, this requires a good amount of Game Master involvement, so it isn’t a guaranteed way to increase you character’s AC.

Being a fantasy game (usually), D&D 5e has a variety of magically enchanted armors which increase a creature’s armor class while wearing them. Of course, the rarer the magic item, the better the bonus. That said, rarer magic items usually require a character to attune to it, but the bonus is usually well worth the attunement slot.

Here’s a list of the different magical armors you can use to increase your character’s AC:

  • +1 Armor
  • +2 Armor
  • +3 Armor
  • +1 Mithral Half Plate
  • +1 Shield
  • +2 Shield
  • +3 Shield
  • Battering Shield
  • Demon Armor
  • Dragon Scale Mail
  • Dragonguard
  • Dwarven Plate
  • Efreeti Chain
  • Elven Chain
  • Glamoured Studded Leather
  • Heward’s Hireling Armor
  • Hide of the Feral Guardian
  • Hunter’s Coat
  • Last Stand Armor
  • Leather Golem Armor
  • Living Armor
  • Obsidian Flint Dragon Plate
  • Powered Armor
  • Ring of Protection
  • Shield of the Hidden Lord
  • Shield of the Silver Dragon

Now, the biggest drawback to relying on magic armor to improve your character’s AC is it’s almost completely up to your Game Master or the module you’re playing to get them. Of course, you can approach your GM and request your character come across a particular magic item, but you can’t guarantee you’ll get it. A good GM should work with you on whether that’s possible in your game, but you also need to understand that you can’t expect your character to get the exact magic item you want them to have.

Be open to what your Game Master will allow and work with them if they feel a particular magic armor wouldn’t work in the game.

Use Cover

Half cover and three-quarters cover give creatures bonuses to their armor class as they use the environment around them to become harder to hit.

Finally, something any creature can take advantage of to improve their armor class is to utilize cover using their environment. Both half- and three-quarters cover confer flat AC bonuses to creatures behind it, so using your environment to shore up your defenses is a great tactic.

Here are the armor class bonuses the different cover types (short of total cover since that makes you usually untargetable) confer:

  • Half Cover: +2 to AC
  • Three-Quarters Cover: +5 to AC

Does Having a High Armor Class Matter?

Having a high armor class is great for most combat encounters. However, it doesn’t help in avoiding damage or effects caused by abilities which force a saving throw. As such, a high AC is ideal but not the end all.

As a Game Master, I’ve ran games for characters with pretty decent armor classes. And yes, targeting them with attacks, both mundane and magical, can be a bit frustrating. But, that’s also the reward for those players who decided to built a high AC character.

You should reward those players for their decision by targeting them with attacks. They’ll love that their high armor class is useful and will make them feel more powerful.

On the other hand, I like to sprinkle in the chaos of targeting high AC characters with saving throw abilities. They’re armor class won’t help stave off a suggestion from a villain to attack their allies, after all. I’ve actually done that.

In my online game, we had a Barbarian with a pretty decent AC. One of the early game bad guys turned them against the rest of the party and it was a great, dramatic moment.

If you’re struggling to deal any damage to the Paladin, Fighter, or Bladesinger Wizard (because they’re AC can get insane), start making them roll saving throws.

The Paladin might have a great Constitution score, but did they dump Dexterity because they didn’t need it for their armor? Sounds like a prime fireball target to me. That Bladesinger Wizard? Yeah, they’ve got a good Dexterity score, but they’re still a Wizard and maximilian’s earthen grasp with it’s forced Strength save is a fantastic way to stop their prancing about.

The point is, I’ve played with high armor class player characters and it’s great to both let them use their great AC but you should also challenge them.

Calculating Armor Class in 5e FAQ

Metal armor resting on chain mail

Does Dexterity Increase Armor Class?

Generally, yes; a higher Dexterity increases a creature’s armor class in 5e. However, there are exceptions like wearing heavy armor.

A creature’s armor class is usually some sort of calculation of a base AC plus their Dexterity modifier. But, that’s not always the case. Medium armor has a limit on how much of their Dexterity modifier applies and heavy armor ignores that modifier completely.

Does Shield Add to Armor Class?

Yes; shields in 5e add a flat +2 bonus to a creature’s armor class.

Simple as that. A shield add a +2 to a creature’s armor class while wielding one. That said, a creature can only benefit from wielding one shield at a time, so they don’t stack bonuses.

Do You Want a High or Low Armor Class?

Generally, characters in 5e want a high armor class to reduce the likelihood of getting hit by attacks. A higher number means your character is harder to hit as enemies need to meet or exceed your total AC when they roll to attack.

A high armor class is great for avoiding damage from attack rolls both mundane and magical. The higher the number, the higher an attack roll needs to be since that roll needs to meet or exceed the target AC.

Can Armor Class Go Above 20?

Yes; armor class can go above 20 in D&D 5e. There are no restrictions on how high you can push your AC given the right abilities.

There is nothing in D&D 5e’s rules which restricts how high armor class can go. Some of the best armor class builds reach as high as 24 perpetually but can go even higher with temporary boosts like the shield spell.


Summary of Calculating AC in 5e

That’s about it for how to figure out your armor class in D&D 5e.

The base, unarmored armor class for any creature equals 10 plus their Dexterity Ability Score modifier. This gets modified depending on what kind of armor type you wear, class features, spells, and a myriad of other modifications. That said, while a high armor class is great for avoiding damage from attack rolls, it doesn’t help in preventing damage or effects which force saving throws.

What’s the highest armor class you’ve reached as a player? How do you get around high AC characters as a Game Master? Leave a comment below to help other players!

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