Ability Checks

The GM calls for an ability check when a character or monster attempts an action (other than an attack) that has a chance of failure. When the outcome is uncertain, the dice determine the results.

For every ability check, the GM decides which of the six abilities is relevant to the task at hand. Some ability checks involve a skill. (77) See the various actions associated with each ability:

Dexterity

*Contest. Sometimes one character’s or monster’s efforts are directly opposed to another’s. This can occur when both of them are trying to do the same thing and only one can succeed, or when one of them is trying to prevent the other one from accomplishing a goal. The outcome is determined by a special form of ability check called a contest. (77)

Working Together

See the passive Wisdom (Perception) check

A successful ability check is calculated as follows:

d20¹ + ability modifier² + proficiency bonus³ + other bonus or penalty ≥ DC of task*

¹ Roll 2d20 if you have advantage or disadvantage. Go here for reasons why either may apply.

² Apply the relevant ability modifier. See also: Variant: Skills with Different Abilities.

³ If the ability check involves a skill, add your proficiency bonus if you are proficient in the skill. If the action requiring a check involves a tool, add your proficiency bonus if you are proficient with the tool. If you don't have or can't use the tool, then you can't make the ability check.