PF2e / SF2e Odds Calculator
A probability calculator for Pathfinder 2e and Starfinder 2e skill challenges, with full degree-of-success maths.
Enter a task DC, your skill modifier, and the successes needed, and see the full odds for a 2e skill challenge:
- Per-roll chances of each outcome — critical success, success, failure, and critical failure — with natural 1 and natural 20 degree shifts applied per the rules.
- Projected rolls to finish, with critical successes counting double.
- Probability of fulfilling the challenge versus breaching within that window, computed via a Markov chain.
Results update as you type, and a toggle switches between Pathfinder and Starfinder presentation.