Free tool
Chess puzzles from your own games
Most puzzle trainers feed you random positions. Audit Chess builds puzzles from your games — the tactics you missed and the blunders you and your opponents actually made — so every puzzle fixes a real weakness in your play.
Why puzzles from your own games work better
Random puzzle sets train general pattern recognition, but they do not fix your blind spots. You keep solving the positions you are already good at while your actual weaknesses go undrilled. That is why many players grind thousands of puzzles and their game rating barely moves.
Puzzles built from your real mistakes work differently. If you keep missing knight forks on f5, you need to see that exact pattern again and again — not a stream of unrelated tactics. Audit Chess surfaces the positions from your history where you went wrong, so every session targets the gaps that are costing you points.
For a deeper look at why targeted training beats random puzzles, see the guide on chess tactics training and how to stop blundering in chess.
How it works
- 1
Enter your username or paste a PGN
Audit Chess imports your games directly from Lichess or Chess.com by username. You can also upload or paste any PGN file.
- 2
Stockfish reviews every game
The engine runs in your browser and evaluates every position move by move, identifying the moments where you or your opponent made a significant error.
- 3
Each error becomes a puzzle
Every blunder and missed tactic is extracted and turned into a puzzle you solve on an interactive board. Solutions are verified by the engine in real time.
What kinds of puzzles you get
FIX
Your blunders
Re-solve positions where you went wrong and find the move you should have played. The engine verifies your answer and shows the best line if you are wrong.
PUNISH
Their blunders
Train yourself to convert the mistakes your opponents hand you. These are positions where they blundered and you missed the refutation — the wins you could have had.
MISS
Missed tactics and mates
Forks, pins, skewers, and forced mates you walked past. Drilling these repeatedly is what makes the patterns automatic in future games.
There is also an adaptive puzzle feed built from the Lichess puzzle database, filtered by opening and theme — useful for filling in gaps your own games have not yet covered.
Want to see it before you start?
The live demo lets you solve a real blunder puzzle with the full Stockfish engine running in your browser — no games or account needed. A wrong answer drops you onto a free analysis board so you can explore the position yourself.
Frequently asked questions
Where do the puzzles come from?+
From your own games. Audit Chess imports your Lichess or Chess.com history, reviews every position with Stockfish, and turns the moves where you went wrong — or where you let your opponent off the hook — into puzzles.
Is it free?+
Yes, completely. Every feature is free with no account required and no limit on how many games you can analyze. It runs entirely in your browser — nothing is uploaded and nothing is stored.
Do I need to install anything?+
No. Audit Chess runs entirely in your browser, including the Stockfish engine. There is nothing to install and no account required.
How is this different from Chess.com or Lichess puzzles?+
Chess.com and Lichess serve puzzles from a shared database of other players' games. Audit Chess builds puzzles from your games specifically — so you are drilling the exact mistakes you make, not random positions from strangers.
What if I want to try a puzzle before analyzing my games?+
The live demo lets you solve a real blunder puzzle with the full engine — no account or game history needed. It is the same board and the same Stockfish engine you will use once your games are loaded.
Audit Chess is free, needs no account, uploads nothing, and is not affiliated with Chess.com or Lichess.