Calculating your armor class (AC) in Dungeons & Dragons 5th Edition (5e) is a crucial aspect of character creation and gameplay. Whether you’re a seasoned adventurer or a novice dungeon master, understanding how to determine your AC is essential for navigating the perils of the Forgotten Realms or any other realm you may find yourself in. In this definitive guide, we’ll unravel the complexities of calculating AC in 5e, providing you with a step-by-step process and clear explanations to ensure you wield your defenses with confidence.
The foundation of your AC lies in your character’s physical attributes and the equipment they wear. The base AC for most characters is 10, representing their inherent agility and ability to dodge attacks. However, this base AC can be modified by a variety of factors, including your character’s Dexterity modifier, armor proficiency, shields, and magical items. Understanding the interplay between these elements is key to maximizing your AC and staying alive in combat.
To delve deeper into the intricacies of AC calculation, let’s examine each factor in detail. Your Dexterity modifier plays a vital role in determining your unarmored AC. If your character has a high Dexterity score, they’ll be more agile and slippery, granting them a higher unarmored AC. Additionally, proficiency in certain armor types can further enhance your AC. Wearing heavy armor, for instance, provides a significant AC bonus but may come at the cost of reduced mobility. Shields offer another layer of protection, adding a fixed bonus to your AC. Finally, magical items, such as the Shield spell or the Ring of Protection, can bestow temporary or permanent AC bonuses, empowering you to withstand even the most formidable attacks.
Dexterity Modifier
The Dexterity modifier is a number that is added to your AC calculation. It is based on your Dexterity score, which is a measure of your character’s agility and reflexes. The Dexterity modifier can be positive or negative.
To calculate your Dexterity modifier, you can use the table below:
| Dexterity Score | Modifier |
|---|---|
| 1 | -5 |
| 2-3 | -4 |
| 4-5 | -3 |
| 6-7 | -2 |
| 8-9 | -1 |
| 10-11 | 0 |
| 12-13 | +1 |
| 14-15 | +2 |
| 16-17 | +3 |
| 18-19 | +4 |
| 20 | +5 |
For example, if your Dexterity score is 14, your Dexterity modifier would be +2. This means that you would add +2 to your AC calculation.
Armor Proficiency
Your proficiency in armor determines how much of its AC bonus you gain. Proficiency with light armor allows you to add the full bonus of the armor to your AC. Proficiency with medium armor allows you to add half the bonus. Proficiency with heavy armor allows you to add only one-quarter of the bonus.
Unarmored Defense
If you are proficient in the unarmored defense fighting style, you can calculate your AC without wearing armor as follows:
| Unarmored Defense |
|---|
| 10 + Dexterity modifier + Constitution modifier |
Shield Proficiency
Shield proficiency is a valuable skill that can significantly improve your character’s defensive capabilities in Dungeons & Dragons (5e). By learning to use a shield effectively, you can gain a significant advantage in combat, protecting yourself from enemy attacks and minimizing damage taken.
To gain shield proficiency, you must meet certain prerequisites. First, you must be proficient in the use of martial weapons. This can be achieved by selecting a class or background that grants proficiency in martial weapons, or by taking the Martial Adept feat.
Once you have met this prerequisite, you can gain shield proficiency through various methods. The most common way is to select a class or background that grants proficiency in shields. Alternatively, you can take the Shield Master feat, which grants proficiency in shields and provides additional benefits related to shield use.
Shield Proficiency Modifiers
Proficiency in shields grants you a bonus to your Armor Class (AC) when you are wielding a shield. The bonus is equal to 2, and it is added to your AC in addition to any other bonuses you may have from armor or other sources.
For example, a character with 10 Dexterity, wearing leather armor (AC 11), and wielding a shield (AC 2) would have an AC of 13. This means that an attacker would need to roll a 13 or higher on their attack roll to hit the character.
| AC Bonus | Source |
|---|---|
| +2 | Shield Proficiency |
| +2 | Leather Armor |
| +1 | Dexterity Modifier |
| 13 | Total AC |
Armor Class (AC) in 5e
Armor Class (AC) represents your character’s ability to avoid or mitigate damage. It is calculated as a combination of your base AC, dexterity modifier, and any other bonuses or penalties you may have.
Heavy Armor and Stealth Disadvantage
Wearing heavy armor grants a high AC bonus, but it also imposes disadvantage on Stealth checks. This is because heavy armor is bulky and noisy, making it difficult to move quietly. The disadvantage applies to all Stealth checks, whether you are actively trying to hide or simply trying to avoid detection.
Calculating AC with Heavy Armor
To calculate your AC while wearing heavy armor, you need to add the armor’s AC bonus to your base AC (usually 10) and your Dexterity modifier. For example, if you are wearing plate armor (AC 18) and have a Dexterity modifier of +2, your AC would be 20 (10 + 18 + 2).
Exceptions to Stealth Disadvantage
There are a few exceptions to the disadvantage on Stealth checks while wearing heavy armor. These include:
| Exception | Description |
|---|---|
|
Expertise in Stealth |
If you have expertise in the Stealth skill, you have advantage on all Stealth checks, regardless of your armor. |
|
Pass Without Trace |
The Pass Without Trace spell grants you and your allies advantage on Stealth checks for 1 hour. |
Overcoming Stealth Disadvantage with Heavy Armor
If you want to use Stealth effectively while wearing heavy armor, you have a few options. You can try to find ways to reduce the noise you make, such as by padding your armor or moving slowly. You can also try to use your environment to your advantage, such as by hiding behind cover or in the shadows. Ultimately, the best way to overcome Stealth disadvantage with heavy armor is to be creative and think strategically.
Natural Armor
Certain creatures have a natural defense against attack. This is called “natural armor.” The Armor Class bonus granted by natural armor depends on the creature’s size and the type of creature it is. For example, a medium-sized dragon has a natural armor bonus of +2, while a huge-sized giant has a natural armor bonus of +4.
Unarmored Defense
Some classes, such as monks and barbarians, can use their Dexterity or Constitution modifier to calculate their Armor Class instead of wearing armor. This is called “unarmored defense.” The Unarmored Defense feature is described in each class’s description.
Calculating AC Without Armor
To calculate your Armor Class without armor, you add your Dexterity modifier and your Constitution modifier to 10. For example, if you have a Dexterity modifier of +3 and a Constitution modifier of +2, your Armor Class without armor would be 15 (10 + 3 + 2).
If you are proficient in the skill, you can also add your proficiency bonus to your Armor Class when you are unarmored. For example, if you are a level 5 monk with a Dexterity modifier of +3 and proficiency in the Dexterity (Acrobatics) skill, your Armor Class without armor would be 17 (10 + 3 + 2 + 2).
Other Factors That Affect AC
There are a number of other factors that can affect your Armor Class, such as magical items, spells, and certain class features. For example, the Shield spell grants you a +5 bonus to your AC, while the Mage Armor spell grants you a +4 bonus to your AC.
Your Armor Class can also be affected by your race and background. For example, the Dragonborn race grants you a +2 bonus to your AC against the breath weapons of dragons, while the Outlander background grants you a +2 bonus to your AC against the effects of being lost or traveling in the wilderness.
Magical Armor and AC Bonuses
Magical armor provides a magical bonus to your AC, which can be added to the base AC of your chosen armor type. The bonus provided by magical armor is typically denoted by a “+X” designation, where “X” represents the bonus value. For example, a suit of magical armor with a “+3” bonus would provide a +3 bonus to your AC.
Additionally, certain items and abilities can provide bonuses to your AC. These include items such as the Shield of Faith spell, which grants a +2 bonus to AC, or the Defensive Fighting Style, which grants a +1 bonus to AC while wearing armor.
Specific AC Calculation Example
To illustrate how these bonuses are calculated, let’s consider the following example:
Let’s say you are a character with a Dexterity score of 16, and you are wearing studded leather armor (base AC 12). You also have a Ring of Protection (+1 bonus to AC) and are under the effect of the Shield of Faith spell (+2 bonus to AC).
Your AC would be calculated as follows:
Base AC (studded leather) + Dexterity Modifier + Ring of Protection Bonus + Shield of Faith Bonus = Final AC
12 + 3 (+1 from Dexterity Modifier) + 1 + 2 = 18
In this example, your final AC would be 18.
Armor Class (AC)
Armor Class (AC) represents a character’s ability to avoid being hit by attacks. It is calculated by adding together the character’s base AC, any bonuses from armor, and any other relevant modifiers:
AC = Base AC + Armor Bonus + Shield Bonus + Dexterity Modifier + Other Modifiers
Cover and Advantage on AC
Cover and advantage can provide significant bonuses to AC, making it more difficult for enemies to hit you. Cover provides a bonus to AC based on the type of cover you have:
| Cover Type | AC Bonus |
|---|---|
| Half Cover | +2 |
| Three-Quarters Cover | +5 |
| Total Cover | +10 |
Advantage on AC gives you a +5 bonus to AC against the triggering attack. Advantage can be gained from a variety of sources, such as being hidden from the attacker, being under the effects of a spell like blur, or having a ranged attacker more than 100 feet away from you.
Combining cover and advantage can provide a significant boost to your AC, making it even more difficult for enemies to hit you. For example, a character with +2 AC from their armor bonus and +2 AC from half cover would have a total AC of 12. If they were also under the effects of the blur spell, which grants advantage on AC, they would have a total AC of 17. This would make them much more difficult to hit, and they would be far more likely to avoid incoming attacks.
Temporary AC Bonuses and Penalties
Temporary AC bonuses and penalties can come from various sources, such as spells, abilities, or equipment. These effects typically last for a limited duration, providing a short-term boost or hindrance to your AC.
Here are some common examples of temporary AC bonuses and penalties:
- Blessing of Protection: This spell grants a +1 bonus to AC for 1 minute.
- Mage Armor: This spell grants a +3 bonus to AC for 8 hours.
- Shield of Faith: This spell grants a +2 bonus to AC for up to 10 minutes.
- Defensive Fighting Style: This Fighting Style grants a +1 bonus to AC while wearing armor.
- Reaction Time: A character with the Reaction Time feat can choose to add +2 to their AC against the triggering attack.
It’s important to note that temporary AC bonuses and penalties stack with each other, regardless of their source. For example, a character under the effects of Blessing of Protection and Mage Armor would gain a total of +4 bonus to AC.
However, temporary AC bonuses and penalties can also cancel each other out. For example, if a character is under the effects of Blessing of Protection and Curse of Vulnerability (which imposes a -2 penalty to AC), the bonuses and penalties would cancel each other out, resulting in no net change to AC.
| Source | Bonus | Duration |
|---|---|---|
| Blessing of Protection | +1 | 1 minute |
| Mage Armor | +3 | 8 hours |
| Shield of Faith | +2 | 10 minutes |
| Defensive Fighting Style | +1 | While wearing armor |
| Reaction Time | +2 | Against triggering attack |
How To Calculate AC 5e
Armor Class (AC) is a measure of a character’s ability to avoid being hit by attacks. AC is determined by the character’s armor, ability scores, and any other bonuses or penalties that apply. AC is calculated using the following formula:
AC = 10 + DEX modifier + armor bonus
For example, a character with a DEX modifier of +2 and wearing leather armor (which has an armor bonus of +1) would have an AC of 13.
There are a few things to keep in mind when calculating AC:
- The DEX modifier is only added to AC if the character is wearing light or medium armor.
- The armor bonus is only added to AC if the character is wearing armor.
- There are a few other bonuses and penalties that can apply to AC, such as the Shield spell or the Defensive Duelist feat.
AC is an important stat for characters in D&D 5e. A higher AC makes it more difficult for monsters to hit the character, which can mean the difference between life and death in combat.
People Also Ask About How To Calculate AC 5e
How can I improve my AC?
There are a few ways to improve your AC, including:
- Wearing better armor
- Increasing your DEX modifier
- Using the Shield spell
- Taking the Defensive Duelist feat
What is the maximum AC I can have?
The maximum AC you can have is 30. This is achieved by wearing plate armor (+3), having a DEX modifier of +5, and using the Shield spell (+5).
What happens if I have a negative AC?
If you have a negative AC, it means that you are more likely to be hit by attacks. For example, a character with an AC of -1 would be hit on a roll of 1 or 2.
