Ability Modifier is a mechanic in Baldur's Gate 3. Ability Modifier is the bonus or penalty you gain from your Ability Score of each Ability. To determine an Ability Modifier, subtract 10 to the Ability Score, then divide the result by two rounded down
Ability Modifier in Baldur's Gate 3
Both Ability Score and Ability Modifiers determines how successful your character is at various things throughout the game. Ability Checks, Attack Rolls and Saving Throws use the Ability modifier to determine the outcome of the bonus or penalty.
To determine an Ability Modifier, subtract 10 to the Ability Score, then divide the result by two rounded down. For example. if you have 20 Strength, your ability score is 21. and your ability modifier (21-10=11) is +5 (11/2=5). If you have 6 Wisdom, then your ability Score is 6 (6 - 10 = -4) and your ability modifier is -2. (-4 / 2 = -2)
Ability Checks are rolled when performing actions within the game world, testing the character's Abilities and often appear in dialogue. When perform an Ability Check, the Ability Modifer for that Ability will be added to the D20 increaseing the chance of success.
Difficulty class is the number you must roll with the D20 to pass the ability check. The task difficulty when performing a DC are:
- Very Easy: 5
- Easy: 10
- Medium: 15
- Hard: 20
- Very Hard: 25
- Nearly Impossible: 30
For Nearly impossible cases, you have to have a very high Ability Modifier, other bonuses and almost a perfect 20 roll on the die.
For example, if you are trying to open a door you cannot open and it has a Strength check DC of 15. Your character has 18 Strength, so he has an Ability Modifier +4. So if you try to force it open, you have to roll the D20 and add +4 to that result. If the result is higher than 15, the door will be forced. However, if you should fail the roll nothing or something bad may happen, like for example jamming the door and making it impossible to open.
All of these operations are calculated by the game automatically, and you can check the results at the bottom of the screen.
Attack Rolls occur when a character is attacking another character. The attacking character rolls the D20 and if the roll is equal or higher than the target's Armour Class (AC), then that attack hits the target with the equipped weapon.
Melee weapons use the Strength ability modifier, while Ranged Weapons use the Dexterity ability modifier. There are some exceptions, such as melee weapons that have the finesse property. These melee weapons use Dexterity instead of Strength.
Saving throws are used to calculate the defense of a character against many effects or Spells in the game. Each of these has its own Difficulty Class (DC), which the character must make a saving throw of the die against in order to protect themselves.
Ability Modifier Table
To determine an Ability Modifier, subtract 10 to the Ability Score, then divide the result by two rounded down as shown in the table below.