See The Mate

See The Mate is a free chess analysis tool that runs the Stockfish 18 engine directly in your browser. Paste a game from chess.com or Lichess, or search by username, and get instant move-by-move evaluation, blunder detection, and opening identification — with no account, no paywall, and no daily limit. Everything happens on your own device: the engine is compiled to WebAssembly and runs inside the browser tab, so there is no server doing the calculation and no queue to wait in. That is also why the site can stay free — there is no per-analysis compute bill to cover.

Is See The Mate really free?

Yes. Every feature — full-depth Stockfish analysis, move classification, the evaluation graph, and unlimited puzzles — is free with no daily cap. There is no premium tier and nothing is locked behind a subscription.

How is this different from chess.com’s Game Review?

Chess.com limits free accounts to one game review per day and reserves full-depth analysis for Diamond members. See The Mate runs Stockfish 18 locally in your browser, so there is no server cost and therefore no limit — you can review as many games as you want at full engine depth.

Do I need to create an account?

No. You can search chess.com or Lichess by username, or paste a PGN or Lichess game URL directly, and start analysing immediately.

Is my game data sent to a server?

No. The Stockfish engine runs as WebAssembly inside your own browser tab. Your moves and positions are evaluated on your device and are never uploaded anywhere.

What do the move labels (Brilliant, Best, Blunder, etc.) mean?

Each move is graded by comparing it to Stockfish’s best move at that position and measuring the centipawn loss — the drop in evaluation caused by your move. Small or zero loss earns Best, Excellent, or Brilliant; large loss is flagged as a Mistake or Blunder, the same scale used by chess.com and Lichess.

What can I do on See The Mate?

Four tools live under one site: Analyze reviews a finished game move by move, Explore is a free sandbox board with live evaluation, Play lets two people share a device for a real offline game, and Puzzles is an unlimited tactics trainer pulled from Lichess’s open database.

Which devices does it work on?

Any modern browser on desktop, tablet, or phone. Stockfish runs slightly slower on older phones since it is limited to the device’s own CPU, but it works — there is no separate app to install.