Everything You Need to Know About Ability Score Improvements (ASI) in 5e
Discover how Ability Score Improvements (ASI) work in Dungeons & Dragons 5e, including how to enhance your stats and the impact on your character’s performance.

Matt Stewart - Wizards of the Coast - Once Upon a Time
Table of Contents
What is Ability Score Improvement (ASI)?
In Dungeons & Dragons 5e, your character’s ability scores are one of the most important factors in determining their performance in combat, skill checks, saving throws, and even social encounters. After your ability scores are determined during character creation, the main way to increase these vital stats is through your class’ Ability Score Improvement (ASI) feature. In this guide, we’ll explore what Ability Score Improvements are, how they work, and how they’ve changed in the 2024 Player’s Handbook.
How Does Ability Score Improvement Work?
At certain levels, your character gains the option to take the Ability Score Improvement feat and improve one or more ability scores of your choice—Strength, Dexterity, Constitution, Wisdom, Intelligence, or Charisma—or choose another feat. When you take the Ability Score Improvement feat, you can gain +2 to a single ability score or +1 to two different ability scores, up to a maximum score of 20.
In the 2024 Player’s Handbook, you also get an Ability Score Improvement from your background. This is a special Ability Score Improvement that allows you to gain +2 to one ability and +1 to another or +1 to three different ability scores.
Ability Score Vs. Ability Modifier
On your character sheet, you will see two different numbers relating to your character’s abilities: ability scores and ability modifiers.
Ability Scores are what you improve using ability score improvements. The total number doesn’t have to do with D20 Tests—it’s more of a reflection of your character’s potential in a particular area, like their raw strength or mental aptitude. These scores range from 1 to 20 for most characters, though magical enhancements, class features, and other effects can push them higher.
These scores are used when determining if you have the proper prerequisites to pick up and certain feat, like Actor, which requires a minimum of 13 Charisma, or a piece of equipment, like Heavy armor, which requires a certain Strength score depending on the armor you’ve chosen.
Ability Modifiers, on the other hand, are the numbers you use when rolling dice. They’re derived from your ability scores, typically calculated by subtracting 10 from your ability score and then dividing by 2 (rounded down).
For example, a Strength score of 16 gives a modifier of +3, which is the number you apply when making Strength-related rolls, such as a melee attack, Strength saving throw, or Strength (Athletics) check.
When Do You Gain an Ability Score Improvement?
Each class in Dungeons & Dragons 5e gains the Ability Score Improvement feature at level 4 and gains additional ASIs according to their class level (not their character level). Here’s a quick breakdown:
Class | ASI Levels |
---|---|
Barbarian | Levels 4, 8, 12, 16 |
Bard | Levels 4, 8, 12, 16 |
Cleric | Levels 4, 8, 12, 16 |
Druid | Levels 4, 8, 12, 16 |
Fighter | Levels 4, 6, 8, 12, 14, 16 |
Monk | Levels 4, 8, 12, 16 |
Paladin | Levels 4, 8, 12, 16 |
Ranger | Levels 4, 8, 12, 16 |
Rogue | Levels 4, 8, 10, 12, 16 |
Sorcerer | Levels 4, 8, 12, 16 |
Warlock | Levels 4, 8, 12, 16 |
Wizard | Levels 4, 8, 12, 16 |
The Impact of Ability Scores on Your Character
Your ability score determines the modifier that applies to various aspects of your character, including attack rolls, skills, and saving throws. These modifiers are essential for calculating your effectiveness in a certain aspect of the game:
- Strength helps you deal damage with most Melee weapons and allows you to wear Heavy armor without impeding your abilities
- Dexterity improves your Armor Class (AC) and attack rolls with Finesse or Ranged weapons, benefiting characters like Rogues who rely on Dexterity for their Sneak Attack damage.
- Constitution dictates your HP, ability to maintain Concentration on spells, and endurance.
- Wisdom increases your ability to notice details with Perception checks or resist magical influences that target your Wisdom.
- Charisma represents your force of personality and is especially valuable for characters like Bards who rely on Charisma for spellcasting and social interactions.
- Intelligence is your knack for knowledge and the arcane.
Ability Score Improvement vs. Feats
In the 2024 Player’s Handbook, the Ability Score Improvement class feature has been turned into a feat. When you gain this class feature at level 4, and each subsequent time you gain this feature, you can either choose the Ability Score Improvement feat or another feat that you qualify for.
Feats are now split into four categories:
- Origin Feats: You typically gain these feats with your background. They do not provide any bonuses to ability scores.
- General Feats: In the 2024 Player’s Handbook, feats that fall into this category all provide a +1 bonus to a related feat. For instance, the Actor feat provides +1 to Charisma.
- Fighting Style Feats: Certain martial classes gain access to this feat category. They do not provide any bonuses to ability scores.
- Epic Boon Feats: Every class gains an Epic Boon feat at level 19. These not only boost an ability score by +1, but your ability score maximum is increased to 30 instead of 20.
When choosing between the Ability Score Increase feat or another feat, make sure you look at the ability scores your class relies on. If you have an odd ability score, gaining a General or Epic Boon feat will not only boost your ability score but also your ability score modifier. If your ability score is an even number, you’ll need to +2 it to increase your ability score modifier.
When to Choose an Ability Score Improvement
Ability Score Improvements are crucial to every character in D&D. As you level up, you’ll face progressively more difficult foes, and you’ll want to make sure your abilities can defeat said foes. But, the focus you put on Ability Score Increases can differ based on your class:
Spellcasters (Artificers*, Bards, Clerics, Druids, Sorcerers, Warlocks, Wizards): These classes only get four Ability Score Increases over the course of their class’ progression and should prioritize getting their spellcasting ability to 20 as soon as possible. Once they reach this point, they can either pump Constitution for additional Hit Points (and help with Concentration checks) or choose a feat to increase their skill set.
Half-Casters (Monks*, Rangers, Paladins): These classes also only get four Ability Score Increases, which is tough because they usually have to pump their spellcasting ability score as well as their martial abilities. While they often rely on their martial abilities, if they want to keep their spellcasting relevant into higher levels, they’ll need to spread their ASIs thin and usually won’t have the chance to pick up other feats.
Martials (Barbarians, Fighters, Rogues): The classes in this category are focused on two things: their damage ability score (Dexterity or Strength) and Constitution. This means they’ll likely have enough resources to get both of their relevant ability scores to 20 and, in the case of Rogues and Fighters, who get more ASIs than any other class, will have resources left over to pick up additional feats.
* These classes don’t actually fall into this category, but their ASI progression reflects the other classes in this category.
Choosing Your Ability Scores
Choosing which ability score to improve is often a balance between enhancing your primary stats and rounding out your character’s weaknesses. For example, a Paladin may prioritize their Strength score for combat effectiveness or Charisma for spellcasting, while a Rogue might improve their Dexterity score to enhance their attack rolls with Melee or Ranged weapons and Sneak Attack potential.
While the most common option is to increase a single ability score, there are cases where you may choose to increase two ability scores by 1 point each, especially if two of your relevant ability scores are odd numbers.
How Magic Items and Other Enhancements Affect Ability Scores
In Dungeons & Dragons, magic items like the Gauntlets of Ogre Power or the Belt of Giant Strength can artificially increase a character’s Strength score, which impacts the related modifier. These magic items provide a temporary or permanent bonus to an ability score, allowing characters to take different feats or help them meet certain requirements for feats or equipment.
Additionally, the Proficiency Bonus—a stat that increases with class levels—further boosts the effectiveness of your ability modifiers and plays a role in your overall performance, especially for saving throws and attack rolls.
You’ve Just Leveled Up Your Intelligence!
Ability Score Improvements are one of the most impactful mechanics in Dungeons & Dragons 5e, enabling players to grow their characters into powerful heroes. While it might not be fun or exciting to spend a feat on increasing your character’s ability scores, it’s often the right choice.
Optimizing your ASI is an essential part of building your D&D character, and we go into the specifics more in our class guides.