What Are Ability Score Improvements & How Do They Work in D&D 5e?

What are ability score improvements?

An ability score improvement (ASI) lets you increase your PC’s stats. In D&D 5e, your player character (PC) has 6 ability scores: Strength, Dexterity, Constitution, Charisma, Wisdom, and Intelligence. Ability score improvements give you the opportunity to add +1 to two of those scores or +2 to one of them—and as your PC’s ability scores improve, they get better at skills, checks, and saves associated with those scores. For example, say your character is a barbarian and needs a high Strength score. By raising their Strength with an ability score improvement, you could also boost their aptitude for Strength-based skills.

Ability score improvements also increase your ability score modifiers. Every ability score has a modifier, which is the value you add to checks, saving throws, and attack rolls. Modifiers are values based on the associated ability score—so the higher your ability score is, the higher your modifier for that score will be. And, if you have a higher modifier, you can add that number to rolls for a better result. Ability scores and their corresponding modifiers are: Ability score 4-5: -3 modifier 6-7: -2 modifier 8-9: -1 modifier 10-11: +0 modifier 12-13: +1 modifier 14-15: +2 modifier 16-17: +3 modifier 18-19: +4 modifier 20-21: +5 modifier

Which levels include ability score improvements?

You can choose an ASI at levels 4, 8, 12, 16, and 19. Ability score improvements aren’t available every time you level a PC up; rather, every class is guaranteed an ASI (or feat choice) at the above levels, meaning you’ll get the chance to have at least 5 ASIs if you level your character all the way up to level 20 (or just 19) over the course of the campaign. Certain classes (namely rogues and fighters) get more ASIs than the rest. Rogues get an ASI at level 10 (for a total of 6 ASIs throughout all 20 levels). Fighters get additional ASIs at levels 6 and 14, for a total of 7 ASIs through level 20.

How to Use Ability Score Improvements

Give one of your PC’s ability scores a +2 bonus. When you give your PC an ability score improvement, you can choose to boost a single ability score by +2—which guarantees that their modifier will also increase. This is an especially helpful move if your PC has an even ability score (since it’ll take 2 points to increase the modifier for that score). Essentially, ability modifiers increase by +1 for every 2 points added to the score. So, if your PC’s Dexterity score is 14 (with a +2 modifier), you could add +2 with an ability score improvement for a Dexterity score of 16 (with a +3 modifier).

Add a +1 bonus to 2 of your PC’s ability scores. Instead of adding a +2 bonus to a single score, you can choose 2 ability scores and give each a +1 bonus if there are multiple scores you’d like to increase. This can be useful if you have more than one odd ability score (since modifiers go up with even-numbered ability scores). For example, if your PC’s Intelligence and Constitution scores are 13 (with a +1 modifier), you could use an ASI to make each score 14 (with a +2 modifier).

Choose a feat instead of an ability score improvement. If you don’t want to give your PC an ability score improvement, you can select a feat—which is an optional extra ability available in place of an ASI. However, be sure to discuss feats with your DM before choosing one for the first time; they might have restrictions or house rules on which feats you can give your PC. Some feats are considered “half-feats,” meaning they give your PC +1 to a certain ability score in addition to an extra ability. For example, Fey Touched is a half-feat because it lets you increase your PC’s Intelligence, Charisma, or Wisdom score (your choice) and lets your PC cast 2 spells.

When should you improve an ability score?

Consider choosing an ASI when your PC’s primary stat is below 20. Since 20 is the maximum value for an ability score (unless you find a magic item that can raise it higher than that), it’s a good idea to get the most important ability score for your PC as close to 20 as possible. Identify your PC’s primary ability score; if it’s an 18 or lower, an ASI can help get you to 20. If your PC’s primary score is 19, you could use an ASI or a feat to raise it to 20 (since some feats offer +1 ability score bonuses). For example, say your PC is a sorcerer, meaning their primary spellcasting ability is Charisma. If your sorcerer’s Charisma is 16 (with a +3 modifier), you could use an ASI to get it to 18 (with a +4 modifier). On a future ASI, you could also raise their Charisma from 18 to 20.

When should you take a feat?

Try a feat if your PC only needs a +1 ability score bonus (or none). Since certain feats grant a +1 ability score bonus, you could take a feat instead of an ASI when you don’t need a full +2 bonus (and you can still get an extra ability along with the ability score boost). Even if you feel like an ASI might be the best option, read through the available feats first; you never know when a particular feat might suit your PC well! You might also take a feat when you deliberately want to raise an ability score to an odd number (potentially because you want to raise it again in the future or because you need a minimum score of 13 to multiclass). At the end of the day, the decision between feat and ASI is completely up to you—and there’s really no wrong answer. Both feats and ASIs can boost your PC’s power and effectiveness (if you’re worried about that) while also giving you new character development and role-playing opportunities. So, choose whichever option you like best!

Ability Score Improvements While Multiclassing

Multiclassing may mean you don’t get ability score improvements as often. Because ASIs happen at specific levels, multiclassing (having your character take on multiple classes instead of just 1) can stop you from reaching each ASI level as fast as you normally would—and you might find that your PC doesn’t get ASIs when the other PCs in the party do. PCs get ASIs at levels 4, 8, 12, 16, and 19, but that doesn’t add up across classes; your PC has to reach each level in a single class to get the ASI. For example, say your PC is a level 3 bard, and you decide to take 1 level in paladin. Your PC wouldn’t get an ASI when taking the level in paladin, even though they’d technically be level 4. Instead, your PC would get the ASI by taking a 4th level in bard or reaching level 4 in paladin. However, you can still get just as many ASIs while multiclassing as you normally would; for example, with 4 levels in paladin and 16 levels in bard, your PC would still get 5 ASIs at the end of the day.

Other Ways to Increase an Ability Score

Magic items can raise an ability score beyond the usual maximum. The only other easy way to raise an ability score is by using a magic item—and there are quite a few your PC might find while exploring a dungeon (or a magic shop). Certain items can increase a particular ability score by a couple of points, while others can boost them over 20 (normally the limit for PC ability scores). For example: Gauntlets of Ogre Power. These gloves can increase your PC’s Strength score to 19. Belt of Giant Strength. There are multiple variations of this belt based on different giant types, each setting a PC’s Strength to anywhere from 21 (Hill Giant) to 29 (Storm Giant). Amulet of Health. An amulet that sets your PC’s Constitution score to 19 while attuned. Headband of Intellect. A crown that sets your PC’s Intelligence score to 19 while attuned. Tomes and Manuals. Six magical books can raise each ability score by +2, from the Tome of Leadership and Influence (Charisma) to the Manual of Quickness of Action (Dexterity).

Ability Scores & Why They Matter

Ability scores measure your PC's physical and mental skills. As mentioned above, the 6 ability scores are Strength, Dexterity, Constitution, Intelligence, Charisma, and Wisdom; your PC's score for each ability determines their aptitude for it and, therefore, their strengths and weaknesses. The higher the score, the better your PC is with a particular ability. Strength measures might and physical power. Dexterity measures agility, reflexes, and speed. Constitution measures health, hardiness, and endurance. Intelligence measures logic, reasoning, and memory. Wisdom measures willpower, perception, and insight. Charisma measures force of personality and the ability to interact with others effectively.

Ability scores impact all checks, saves, and attacks. Ability checks are rolls that determine whether your PC can overcome a challenge (related to a particular ability score). Saving throws determine their ability to resist harmful effects, and attack rolls measure their ability to strike enemies. Since every check, save, and attack is tied to an ability score, your PC's ability scores (and improvements) matter! For example, if your PC were grabbed by an ogre, they might make a Strength check to try and break free. If your PC has a low Strength ability score (and a negative modifier), that means they're physically not very powerful—and their Strength check is more likely to be low as well. If they have a high Strength score and bonus, that means your PC is physically powerful and more likely to break free of the ogre's grip.