Calculating Armor Class in Dungeons & Dragons 5th Edition
In Dungeons & Dragons 5th Edition (5e), Armor Class (AC) is a crucial defensive statistic that determines how difficult it is for opponents to land attacks on a character. Calculating AC involves adding together various modifiers, including those from armor, shields, dexterity, and other sources. This article will guide you through the process of calculating AC in 5e, ensuring your character is as protected as possible.
Understanding Armor Class
Armor Class represents the overall defensive capability of a character, combining the protection provided by armor, shields, and other factors. It's expressed as a number, with higher values indicating better protection. When an attacker makes an attack roll, they must roll a d20 and add their attack bonus. If the total is equal to or higher than the target's AC, the attack hits. Otherwise, it misses.
Base Armor Class
The base AC for an unarmored character is 10 + their Dexterity modifier. This is because Dexterity represents a character's agility and reflexes, making it easier for them to dodge incoming attacks. For example, a character with a Dexterity score of 16 (+3 modifier) would have a base AC of 13.

Armor and Shields
Armor and shields provide additional protection, increasing a character's AC. The type of armor worn determines the AC bonus it grants. Light armor provides a +10 to +13 bonus, medium armor provides a +11 to +18 bonus, and heavy armor provides a +14 to +19 bonus. Additionally, shields can grant a +2 bonus to AC if the character is proficient with shields.
Example: Calculating AC with Armor and Shield
Let's say we have a character with the following stats:
- Dexterity: 16 (+3 modifier)
- Wearing Plate Armor (AC 18)
- Using a Shield (AC +2)
The character's AC would be calculated as follows:

| Base AC | Armor Bonus | Shield Bonus | Total AC |
|---|---|---|---|
| 10 + 3 = 13 | +18 | +2 | 13 + 18 + 2 = 33 |
So, this character's total Armor Class would be 33.
Other Sources of AC
In addition to armor and shields, other sources can temporarily or permanently increase a character's AC. These include:
- Dexterity bonuses from spells like Mage Armor or Shield of Faith.
- Temporary bonuses from effects like the Bless spell or the Blessed condition.
- Permanent bonuses from feats, class features, or racial traits.
When calculating a character's AC, be sure to include all applicable bonuses from these sources.
Conclusion
Calculating Armor Class in 5e involves understanding the various factors that contribute to a character's defensive capabilities. By combining base AC, armor and shield bonuses, and other applicable bonuses, you can ensure your character is as protected as possible. Always remember to include all relevant bonuses when calculating AC to maximize your character's survivability.