Fix Your Chess Mistakes
Turn your game review into practice. Chessda puts you back in the position right before each of your blunders, mistakes, and missed chances and asks you to find the move you should have played — graded live by Stockfish, all in your browser.
Practise your real mistakes — no account, nothing to install.
The fastest way to improve at chess is to stop repeating your own mistakes. Most tools show you where you went wrong; this one makes you fix it — it drops you back into the exact position before each blunder and asks for a better move. Review a game to start →
How it works
- Review a game — paste a PGN or import by Chess.com / Lichess username.
- Hit “Fix your mistakes.” Chessda collects your blunders, mistakes and missed chances.
- Find the better move at each position; Stockfish grades it live and you retry until you get it.
- See how many you fixed — worst mistakes first.
Why drill your own games?
- You practise the exact errors that cost you rating, not generic puzzles.
- Retrying the real position builds the habit of finding the move under your own conditions.
- It’s free and private — the engine runs on your device, nothing is uploaded.
Frequently asked questions
What is the “fix your mistakes” chess trainer?
After Chessda reviews your game, it builds a drill from your own errors. You’re put back in each position right before a blunder, mistake, or missed chance and asked to find the move you should have played — Stockfish checks your answer in your browser.
How is this different from a normal puzzle?
Normal puzzles are someone else’s positions. This drills your real mistakes from your real games, so you’re practising the exact things that cost you points — the fastest way to stop repeating them.
Do I need an account?
No. The whole drill runs in your browser with no sign-up. Review a game (paste a PGN or import by username), then hit “Fix your mistakes.”
What counts as fixing a mistake?
Playing a sound move — the engine’s best, or close enough that you no longer give anything away. If your move isn’t good enough, it just says “try again” and lets you keep looking; you can reveal the better move whenever you’re stuck.
Which mistakes does it drill?
Your blunders, mistakes, missed wins, and inaccuracies — worst first — for whichever side you choose. Brilliant and best moves aren’t mistakes, so they’re left out.