Pathfinder Ability Score Modifier Calculator
Enter an ability score to calculate its modifier, used for attack rolls, saving throws, skill checks, and more in Pathfinder RPG.
Enter an ability score above and click Calculate.
Formula
Modifier = floor((Ability Score − 10) ÷ 2)
Examples:
- Score 10 → floor((10−10)/2) = +0
- Score 16 → floor((16−10)/2) = +3
- Score 8 → floor((8−10)/2) = floor(−1) = −1
- Score 1 → floor((1−10)/2) = floor(−4.5) = −5
Assumptions & References
- Source: Pathfinder Core Rulebook, Paizo Publishing — Ability Scores chapter.