Proficiency

Characters and monsters are good at various things. Some are skilled with many weapons, while others can use only a few. Some are better at understanding people’s motives, and others are better at unlocking the secrets of the Great Wheel. All creatures have a Proficiency Bonus, which reflects the impact that training has on the creature’s capabilities. A character’s Proficiency Bonus increases as the character gains levels. A monster’s Proficiency Bonus is based on its Challenge Rating. The Proficiency Bonus table shows how the bonus is determined.
This bonus is applied to a D20 Test when the creature has proficiency in a skill, in a saving throw, or with an item that the creature uses to make the D20 Test. The bonus is also used for spell attacks and for calculating the DC of saving throws for spells.

Proficiency Bonus

• Up to 4 (+2)

• 5–8 (+3)

• 9–12 (+4)

• 13–16 (+5)

• 17–20 (+6)

• 21–24 (+7)

• 25–28 (+8)

• 29–30 (+9)

The Bonus Doesn’t Stack

Your Proficiency Bonus can’t be added to a die roll or another number more than once. For example, if a rule allows you to make a Charisma (Deception or Persuasion) check, you add your Proficiency Bonus if you’re proficient in either skill, but you don’t add it twice if you’re proficient in both skills.
Occasionally, a Proficiency Bonus might be multiplied or divided (doubled or halved, for example) before being added. For example, the Expertise feature doubles the Proficiency Bonus for certain ability checks. Whenever the bonus is used, it can be multiplied only once and divided only once.