♟ Checkmate Mind

Puzzle scanner

Upload a screenshot of the puzzle board (Lichess / Chess.com–style: board centered, filling most of the frame), add a Gemini API key for Read FEN and the embedded AI chat (ChatGPT itself can’t be embedded here — link below). Then add what you said, then compare your move to Stockfish over http://.

If anything looks off, skip scanning: on Lichess open the puzzle or analysis board and copy the FEN from under the board — paste it in the box on the right. That path is boring but reliable; image reading is best-effort only.

Board scan does not work on real boards. It was trained on flat screenshots from sites like Lichess or Chess.com (board large and centered, no perspective). Photos from above the table, shadows, or 3D boards usually read as nonsense — use the site’s copy FEN or a tight crop of the on-screen board only.

Video: no in-browser transcription of uploads — paste a transcript or Dictate (Chrome / Edge). Castling / en-passant are filled as “none” after a scan — edit if needed. MIT: Elucidation/ChessboardFenTensorflowJs.

AI board reader (Gemini)

Vision API

Get a key from Google AI Studio (free tier). It stays in your browser only (localStorage) and is sent only to Google when you use Read FEN or the AI chat — not to Checkmate Mind.

Puzzle image

Upload

With a Gemini key, the image is sent to Google’s vision API first. Otherwise we crop to 256×256 and use offline template + neural fallback.

Loading board reader…

Position (FEN)

Auto or paste

Choose who is to move. You can paste the full line from Lichess’s analysis bar, or only the piece part (before the first space) — we add w/b - - 0 1 from your side choice.

AI chat (embedded)

Gemini

ChatGPT cannot be embedded on this page (OpenAI blocks iframes and browser API calls). Below is a chat-style panel that talks to Google Gemini with the same API key — upload your board, then ask for FEN, ideas, or “what if I play …?”.

Use ChatGPT instead? Open ChatGPT in a new tab, click the paperclip, attach your screenshot, and ask for the FEN — that’s the official product (not embeddable here).

If the image reader fails

Reliable paths

Image-to-FEN is finicky everywhere for 3D boards and messy crops. For puzzles, don’t depend on scanning — use one of these, then paste the FEN here.

  1. Easiest: On Lichess analysis or your puzzle tab, copy the FEN from the box under the board (or use the share / editor menu). Paste the full line into the FEN field above — that is the most reliable method.
  2. Recreate the position: Open Lichess board editor (or Chess.com analysis), set up the pieces to match your puzzle, choose side to move, then copy FEN. Yes — “scanning” by rebuilding the board is slower but almost always correct.
  3. Other image tools (third-party; same rough limits as ours on photos): Chessboard FEN (TensorFlow.js demo) — same idea as our reader; ChessConverter — desktop-oriented, can fix pieces and flip boards. Copy their FEN output back here.

Checkmate Mind is not affiliated with these sites; links are for convenience.

Your thinking

Transcript

Optional video for your own preview only — paste the words underneath, or use Dictate (speech-to-text in supported browsers).

Scan

Stockfish