The Chessy Chess Openings Dataset

Chessy's chess openings dataset covers 3,504 named openings, gambits, traps and anti-openings, of which 2,716 carry at least 50,000 real Lichess games and 3,462 carry Lichess statistics of any volume — every one paired with a Stockfish depth-16 evaluation and, where relevant, a catalogue of the most common human mistakes.

This page is the canonical landing point for every dataset behind Chessy's stats studies: opening win rates, gambit ROI, and common opening mistakes. Each file below is a flat CSV/JSON export of one computed study, ready to load into a spreadsheet, notebook, or another site's own analysis — no scraping or API key required.

What's in the data

Every row traces back to two sources: the Lichess Opening Explorer (win/draw/loss percentages and game counts from real rated games in the blitz and rapid pools, 1200–1600 rating bands) and Stockfish (position evaluation in centipawns, computed at search depth 16, plus the engine's best continuation). Mistake data is derived by comparing each opening's most-played human continuations against Stockfish's best move and classifying the gap as an inaccuracy, mistake, or blunder.

Files available

Nine data files across three studies: four opening win-rate cuts (best for White, best for Black, highest draw rate, most played), one gambit ROI ranking, and four mistake-pattern aggregates (by move class, worst openings, highest average loss, most-punished individual moves). Each has a matching .csv and .json with identical rows.

License and attribution

All data on this page is released under CC BY 4.0 — free to use, adapt, and republish with attribution. If you use this dataset, please link back to trychessy.com/stats.

Download the data

Free to reuse under CC BY 4.0 — please link back to this page.

opening-win-rates-best-white.csv opening-win-rates-best-white.json
opening-win-rates-best-black.csv opening-win-rates-best-black.json
opening-win-rates-highest-draw.csv opening-win-rates-highest-draw.json
opening-win-rates-most-played.csv opening-win-rates-most-played.json
gambit-roi.csv gambit-roi.json
mistakes-by-move-class.csv mistakes-by-move-class.json
mistakes-worst-openings.csv mistakes-worst-openings.json
mistakes-highest-avg-loss.csv mistakes-highest-avg-loss.json
mistakes-most-punished-moves.csv mistakes-most-punished-moves.json

Methodology: win rates and game counts from the Lichess Opening Explorer (blitz + rapid games, 1200–1600 rating bands); position evaluations from Stockfish at depth 16. Snapshot: July 2026. See the full dataset methodology for details.