blunder.zone

by chess lovers, for chess lovers

Your games. Clearer lessons.

Understand your mistake. Practise the better move.

Turn critical moments from your Chess.com and Lichess games into training. Solve a game puzzle, request an AI explanation, and explore the better continuation.

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Blunderzone Game Tactics screen showing a chess position from a player's own game
A real missed position, ready to solve.

From your game to your next lesson

Solve it. Understand it. Practise it.

Bring your games

Connect Chess.com or Lichess. Blunderzone turns critical moments from eligible games into puzzles.

Ask why

Solve a game puzzle, then choose Explain. Read the AI explanation in your chosen language and play through the original and better continuations.

Return to the position

Practise the better move and revisit your positions with spaced repetition.

How Free works

Inside Explain

Why challenge the centre first?

In this real game position, Black played Be7. The better move was cxd4. Here is what Blunderzone explains.

Real Blunderzone position viewed from Black’s side: the c5 pawn can capture White’s pawn on d4 instead of retreating the d6 bishop to e7.
Black to move · Be7 played · cxd4 recommended

Actual AI explanation · excerpt

What went wrong

Be7 is too passive: it postpones the central break and permits Nxf6+, allowing White to simplify Black’s active kingside pieces without first being challenged in the center.

Why the best move is better

cxd4 immediately challenges the center. Following the recapture, ...e5 drives the centralized knight away, giving Black useful activity and room to develop the c8-bishop.

The continuation illustrates best play and is not forced. In the app, you can play through both lines.

This is a static example from the app. Explain is requested after solving a game puzzle; it does not automatically annotate every move. An explanation may take time to prepare.

Train at your own pace

Free forever. More when you want it.

Keep using your Free account for as long as you like. When you want more, paid options offer deeper engine analysis and more AI explanations. See Membership for the full comparison and details.

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Make your next mistake useful

Start free in your browser or use the mobile app with the same Blunderzone account.

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