D&D Proficiency Bonus Calculator
Calculate your D&D 5e proficiency bonus by character level.
See exactly what it applies to and the full level 1–20 reference table.
What Is the Proficiency Bonus?
The proficiency bonus is a flat bonus added to any roll where your character has training or expertise. It starts at +2 at level 1 and increases every four levels, reaching +6 at level 17.
Formula
Proficiency Bonus = 2 + floor((Level − 1) ÷ 4)
So a level 1 character gets +2, a level 5 character gets +3, and a level 17 character gets +6.
What It Applies To
Your proficiency bonus is added to:
- Attack rolls with weapons or spells you are proficient with
- Saving throws your class grants proficiency in
- Ability checks (skills) you are proficient in
- Spell Save DC (8 + Proficiency Bonus + Spellcasting Modifier)
If you have Expertise (Rogues, Bards), you double your proficiency bonus for certain skills. You never add proficiency bonus twice to the same roll — just once (or doubled for Expertise).
Full Proficiency Bonus Table
| Levels | Proficiency Bonus |
|---|---|
| 1–4 | +2 |
| 5–8 | +3 |
| 9–12 | +4 |
| 13–16 | +5 |
| 17–20 | +6 |
Practical Example
A level 7 Fighter with a +3 STR modifier attacks with a longsword they are proficient with. Attack bonus = +3 (STR) + +3 (Proficiency, level 7) = +6 to hit.