🏆Tournament Win Probability Calculator

Enter participants and skill ratings to simulate a single-elimination bracket and get each player's win probability.

runs

Tournament Win Probability Calculator Guide

The Tournament Win Probability Calculator estimates each entrant's chance of winning a single-elimination bracket using Monte Carlo simulation. Plug in player names and 1–100 skill ratings, choose a bracket size, and the tool runs thousands of simulated tournaments to surface statistically stable win odds. Use it for esports predictions, sports brackets, or in-office competition planning.

Each head-to-head match resolves with probability skill_i / (skill_i + skill_j). For example, an 80 vs 20 matchup gives the favorite an 80% chance of winning that round. The tool defaults to 10,000 simulations — increase for stability or decrease for speed.

Bracket sizes of 4, 8, and 16 are supported. Results are sorted by win probability so you can spot the favorite at a glance, while underdogs still surface with their realistic non-zero chance to advance.

Frequently Asked Questions

How are win probabilities calculated?

Head-to-head uses skill_i/(skill_i+skill_j); the bracket is simulated 10,000 times.

How should I set skill values?

Any 1–100 scale that captures relative strength works.

Why doesn't the top seed always exceed 50%?

Winning requires sweeping every round, so probability compounds downward fast.