♟ Blundermind
Stop getting blundermined.
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Solo Play & Explore
Play alone, explore positions, and train board vision with all the indicators.
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Build a Bot
If chess bots don't feel realistic, build your own. Create a bot you enjoy playing against. Practice favorite openings. Hone bullet skills against bots that panic under time pressure, or build ones that keep their cool as they try to flag you.
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2-Player Online
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Upload a PGN file and replay or explore any game move by move.
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Upload a bot configuration file to restore a custom opponent.
Black
Move 0 / 0
White
▶ your move
Black
Notation
No moves yet
White
⚑ Resign
½ Draw
🎨

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About & Feedback

Nearly all games of chess I play are decided on blundered pieces. I created this site in the hopes that I could see what it was like to play a game that was decided by strategy instead of blunders. I still blunder, but at least the number of blunders is reduced a bit when there is a big red circle around the queen when I hover it over my intended square. I still have no idea if this will translate to better board vision in ‘real’ OTB games.

I also struggle with “getting a grip on the board” (to steal a useful phrase from the Chess Dojo), so while my intent was to blundercheck moves so that I would see if I were hanging my queen, I’m finding that it is showing discovered attacks and potential forks that I didn’t see at all (you can probably infer my rating at this point). I think it could be a very helpful tool as long as it is used as a blundercheck to double check and provide immediate feedback after assessment and calculation, not as a blunder avoider that just circles some hanging pieces while potential moves are explored by dragging the pieces around.

Also included in my numerous struggles is the ability to predict my opponent’s response, so I added a feature to show two potential responses by making two calls to Stockfish. I would like to do this with Maia, but running Maia3 on each potential move is too slow with my current set up — hopefully in the future. Currently the site does not include any engine analysis or indicators to show if a move is “good or bad” during game play or exploration. Each game can be downloaded and analyzed in Lichess or a website of your choice. Similarly, the PGN of any game can be uploaded and explored here.

While I most enjoy playing people in person, I find playing strangers online less enjoyable, so I added in the feature to play against bots. The problem with the bots I’ve found is that they don’t feel time pressure, and their behavior is often sporadic in an unsatisfying way. I’ve tried to make the bots customizable in a way so that I have more control over how the bot will play.


Privacy

Blundermind collects no user data, uses no cookies, stores no game history, and tracks nothing. The board set up/configuration and customized bots can be downloaded and stored, then uploaded for future use.


Feedback

Any problems with functionality would be helpful, but I would particularly love feedback on whether any features on this site seem to translate into improvement in ‘real’ over-the-board play.


© 2026 Blundermind. All rights reserved.
Board vision training for we happy few that strive for mediocrity.
Staunton pieces: react-chess-pieces (ISC) · RhosGFX pieces: CC0 · @RhosGFX

🤖 Play vs Bots

Opponent Type

8
4
Engine degrades from starting level → this level when clock is low
None High
Always plays at selected level

Opening Behavior

Time Behavior

Entropy-based delay from pace slider
40
Think time varies with position complexity (entropy)
Stays near top move even when flagging
+ increment (sec)
Untimed

Bot Configuration

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