The 8,400-game calibration.
Seven skill presets. Every pairing. 700 ms per move. Real engine games, saved one by one in your browser.
Strictly legal recorded moves
— capped games
Run the tournament
Pause after game saves your current match. Stop now discards only the unfinished match. Completed games are checkpointed automatically.
Estimated relative strength
Regularized, color-adjusted Bradley–Terry Elo. Training partner = 0. These are not WSA or human ratings.
21 matchups
| Pair | Games | Score (left–right) | Caps / draws | Progress |
|---|
Own your results
Games are stored in IndexedDB on this browser, for this exact website address. They are not automatically synced to Cloudflare or other devices.
Export a backup regularly. Private/Incognito windows and browser cleanup may erase local progress. Import rejects conflicting game IDs instead of silently overwriting them.
What happened
Important limits
The browser must stay open and active. Switching apps, locking your phone, or closing the tab can suspend computation. A new deployment to a different *.pages.dev address does not carry over IndexedDB; export and import your data.
Each engine uses genuine Fairy-Stockfish WASM; hosting the site doesn't make Cloudflare run the tournament for you. Use a computer for extended runs when possible.