Terms of use

ChessMate Central is a free tool for reviewing chess games. It reads games you import from chess.com or paste as PGN, analyses them with the Stockfish engine running in your browser, and reports what each move cost. There is no account, no subscription, and no server holding your games.

The tool comes with no warranty of any kind. In particular:

• Grades and evaluations come from a search to a limited depth. They are an engine's opinion, not a verdict, and a deeper search sometimes disagrees.
• Move classifications are thresholds applied to that opinion. A move on the edge of two grades could reasonably be called either.
• Nothing here promises the site will be available, correct, or free of faults.
• Analysis is a learning aid. It is not a ruling on a game, a player, or a position.

This is the one rule worth stating on its own. Do not use this, or any engine, during a game you are playing. Engine assistance in a live game is cheating. It is against the rules of every serious chess site, it is unfair to the person across the board, and it will get your account closed.

The tool is built for the position you have already lost, not the one you are still in.

• Analyse games you have a right to analyse — your own, or games that are public.
• Respect chess.com's terms when importing from chess.com, including the rate at which their API is used. This tool requests one month of games at a time, in sequence, for that reason.
• Do not use the tool to break the rules of a site you play on.
• Do not attempt to overwhelm, disrupt, or misuse the service.

Game data imported from chess.com belongs to the players and to chess.com, and their terms govern it. ChessMate Central is not affiliated with, endorsed by, or connected to chess.com.

The engine is Stockfish, free software under the GNU General Public License v3, loaded here as a separate WebAssembly worker and unmodified. The board and move handling use open-source libraries under their own licences. The rest of the site — its design, copy and code — belongs to its author.

To the extent the law allows, the author of this tool is not liable for any loss arising from using it. That includes games lost after following its advice, decisions taken on an incorrect evaluation, and any time the site is unavailable. It is a free tool for looking at chess games; treat it as one.

These terms may change. The date at the top of this page says when they last did, and continuing to use the tool after a change means accepting the current version.