If you’re planning on riding into a battle, sword at the ready – kicking ass, and taking names – you have to wear proper gear! Combat is a staple of tabletop RPGs like Dungeons & Dragons, and the armor your character wears is the only line of defense between them and the, potentially fatal, enemies’ attacks.
This is exactly why Armor Class (AC) is one of the most important mechanics of DnD 5e. It can really make or break a character during combat. I mean, if a wolf is coming at me, I’d rather them get a mouthful of leather armor than my character have a piece missing, wouldn’t you? So, in order to protect your character properly, you should learn everything you need to know about Armor Classes as soon as possible. And luckily, I’m here to help.
In this guide, I will teach you the basics of AC – how it works, how to calculate it, and lastly, all the factors that influence it – so your character can breeze through every combat. Now let’s get started!
AC Hits Explained
So, you might ask yourselves – why is AC so important in terms of game mechanics? Well, in combat you need to roll a d20 every time you wish to attack an opponent and then the DM says whether you’ve hit them or missed. That’s exactly when AC comes into play – in order to make their judgement the DM has compared your d20 roll to the defender’s AC. If, for example, you’ve rolled an 18 against the AC of 15, your hit was successful. This is easy enough, right? But what happens if the creature’s AC is also 18? Did you hit them or not?
The DnD community is kinda split on this one and there are essentially two schools of thought – one has a “meets it = beats it” mentality, while the other one requires the attacker to surpass the AC value in order to be successful.
Essentially, you can use both of these versions, but the official rules, from the 3rd edition on, are on the lenient side and require the roll (+ attack bonus ofc) to equal or exceed the AC in order to hit.
How to Calculate Armor Class
If your character is unfortunate enough to walk around without any armor or a shield on hand, they will still have an Armor Class, but it won’t do much help with fending off attacks.
This is called a base AC and is equal to 10 + a character’s Dexterity modifier. But, keep in mind that even though you’re not taking into account any gear, you still need to take your character’s feats, class features, or magic items they’re carrying into consideration (if, of course, they have some sort of effect on their AC).
On the other hand, if your character is wearing armor and/or carrying a shield, you need to include them in the calculation. There are three armor types – light, medium, and heavy – these are made of different materials, they give players various amounts of coverage and therefore also different AC scores. If you want to learn more about the different types of armor available to you in the world of DnD, we have a great guide on that! (LINK HERE)
If you want to be the ultimate badass and also carry a shield, just remember that it always adds +2 to your AC – this will make your life a whole lot easier.
AC of Monsters and Other Creatures Explained
What about creatures, NPCs, and other enemies you come across during your adventures? I mean, if your party is traveling down a dirt road and a band of orcs jumps out of a bush and attacks them – I would expect them to be wearing some sort of armor, wouldn’t you? For monsters and NPCs with armor and shields, you use the same calculation as for PCs, but what about if your party angers a bear or a wolf? It wouldn’t make any sense for them to have any armor. That’s why some beasts and other monsters have natural armor which you can find in their stat blocks and need to add the Dexterity modifier to.
AC of Objects
This might come as a surprise to you, but objects in DnD 5e also have their own AC which depends on the material/substance they’re made of. They also have hit points too, which depend on their size. So next time you want to break into a wooden door or jump through a window, remember you’ll have to have a bit of luck with the d20 roll. To find ACs of common materials, consult Chapter 8 of the Dungeon Master’s Guide.
What Influences Armor Class in 5e
Since we’ve established the importance of a high AC score in DnD 5e, let’s see all the ways you can increase it. There are some you have to think about when creating your character aka before the game even starts, and others, that you can apply at any time during the campaign.
Choose a Race with a Strong Natural Armor
If you’re still in the character creation stage and want to make one with a good AC, then you should consider choosing one with good natural armor. Some examples are locathah and loxodon with 12 + Dex, then lizardfolk with 13 + Dex, and of course, tortle with a whopping 17 + Dex AC.
Pick a Class with Cool Features
Some classes in DnD 5e have class features that make their base AC a bit higher than the other characters (if they’re not wearing any gear). The base AC of monks equals 10 + Dex + Wis, for the barbarians, is 10 + Dex + Con, and, lastly, sorcerers of a Draconic Bloodline get a base AC of 13 + Dex.
Also, fighters who go the Defensive Duelist route get +1 AC when wearing armor. Similarly, Forge Domain clerics get +1 AC when donning heavy armor.
Feats
I know that DnD players are very divided on feats – some love ‘em, others can’t stand ‘em. Well, I’m a feat-lover through and through. If you want a high AC, then maybe you should give some of these a chance. There’s the Defensive Duelist which lets you use up a reaction to add your proficiency bonus to your AC value, Dual Wielder which offers a +1 bonus to AC when handling two weapons, and the Dragon Hide feat gives a higher base AC value to Dragonborns. Also, Lightly, Moderately, and Heavily armored feats give characters proficiency with the corresponding type of armor.
Wear Better Armor
This sounds super obvious, but I’ll say it anyway – if you are profficient in multiple types of armor, wear the one that will give you the best AC. Also, if possible, add a shield for an additional 2 AC points.
Increase Your Dexterity Modifier
You can achieve this through a spell like Enhance Ability or Guidance, also if you’re carrying a Dexterity boosting magic item, or simply through Ability Score Improvement. You can also look at our Initiative guide for more examples of how to increase your Dex modifier! (link here)
Cast a Spell
Spells are not a permanent solution by any means, since their effects will expire sooner or later but they can come in clutch during combat, so they’re worth mentioning.
Mage armor, Shield of Faith, Warding Bond, Shield, Barkskin, and Haste are just a few examples of spells that can boost your AC – there are so many more available out there.
Magical Items
There are a ton of magical items that can give you an AC boost, but I’m just going to name a few here.
Bracers of Defense will give a character who wears them a +2 bonus to AC if they’re not wearing any armor or carrying a shield. A sorcerer, warlock, or wizard can use the Staff of Power which will also give them +2 AC points. If you have some sort of Defender sword, you can also choose to get +1 to damage rolls and +2 to AC instead of the standard +3 to attack and damage rolls.
Take Cover
If all else fails, and you’re caught with no armor during combat, then you should scramble to find cover as quickly as possible because it will make a barrier between you and your opponents.
There are three types of cover in 5e – half cover, three-quarters cover and total cover and each of those gives your character different levels of protection. Total cover blocks most (if not all) of enemies’ attacks but doesn’t impact the character’s AC or Dexterity saving throws. If your character’s almost completely covered but not quite (three-quarters cover), then they get a +5 bonus to AC and Dexterity saves. Lastly, a half cover brings a +2 bonus to AC and Dexterity saving throws.
On the other hand, there aren’t that many things that can decrease a creature’s AC, but I’ll mention the spell Slow which halves the target’s speed and lowers their AC and Dexterity saving throws by 2.
