Engines are flawless, humans play FlawChess
Find and fix the flaws in your game. Free full-game analysis of every chess.com and lichess game: tactics, openings, endgames, and time management.
Game and Tactic Analysis
- Run Stockfish over your entire chess.com and lichess history.
- Understand, replay, and learn from your blunders: mistakes are tagged with the tactic behind them (fork, pin, skewer, and 20+ motifs).
- Track your blunder rate over time, and see how often you fall for each tactic versus your opponents.
- Filter your whole game history by tactic, depth, and severity.
Game and Tactic Analysis
- Run Stockfish over your entire chess.com and lichess history.
- Understand, replay, and learn from your blunders: mistakes are tagged with the tactic behind them (fork, pin, skewer, and 20+ motifs).
- Track your blunder rate over time, and see how often you fall for each tactic versus your opponents.
- Filter your whole game history by tactic, depth, and severity.
Opening Explorer & Insights
- Get a detailed statistical analysis for every move you’ve played.
- Compare your win/draw/loss rate to the Stockfish evaluation at the end of the opening.
- Scan the first 8 moves of all your games to surface opening strengths and weaknesses.
- Scout your opponent's repertoire before a match.
Opening Explorer & Insights
- Get a detailed statistical analysis for every move you’ve played.
- Compare your win/draw/loss rate to the Stockfish evaluation at the end of the opening.
- Scan the first 8 moves of all your games to surface opening strengths and weaknesses.
- Scout your opponent's repertoire before a match.
Endgame Analytics
- Measure how well you convert winning endgames and recover from losing ones.
- Track your Endgame ELO over time by platform and time control.
- Get personalized feedback on what your stats mean.
Endgame Analytics
- Measure how well you convert winning endgames and recover from losing ones.
- Track your Endgame ELO over time by platform and time control.
- Get personalized feedback on what your stats mean.
Time Management Stats
- See your average time advantage or deficit when entering the endgame.
- Find out if you crack under time pressure more than your opponents.
- Compare your flag rate to your opponents' per time control.
Time Management Stats
- See your average time advantage or deficit when entering the endgame.
- Find out if you crack under time pressure more than your opponents.
- Compare your flag rate to your opponents' per time control.
Opening Comparison and Tracking
- Bookmark your favorite openings and compare their performance.
- See how your opening study impacts your win rate over time.
- Filter by time control to find which openings work best where.
Opening Comparison and Tracking
- Bookmark your favorite openings and compare their performance.
- See how your opening study impacts your win rate over time.
- Filter by time control to find which openings work best where.
System Opening Filter
- Group system openings (like the London) across all variations.
- Filter by your pieces only, ignoring opponents' responses.
- Get win/draw/loss rates for the entire system, not scattered names.
System Opening Filter
- Group system openings (like the London) across all variations.
- Filter by your pieces only, ignoring opponents' responses.
- Get win/draw/loss rates for the entire system, not scattered names.
🏗️ Under active development. Bug reports and feature requests are welcome on GitHub or via support@flawchess.com.
Frequently asked questions
Acknowledgements
FlawChess is built with and inspired by these projects:
- Lichess — open-source chess platform and game data API
- Chess.com — chess platform and game data API
- OpeningTree.com — inspiration for position-based opening analysis
- ChessGoals — cross-platform rating comparison data
- python-chess — chess logic, move generation, and Zobrist hashing
- Stockfish — open-source chess engine for position evaluation
- FastAPI — async Python web framework
- chess.js — chess move validation and game state
- react-chessboard — interactive chessboard component
- Recharts — composable chart library
Free to use. No credit card required.