Applies to the Chess Coach browser extension for Chrome and Firefox. Last updated 16 October 2026.
Chess Coach collects no personal data. It has no account, no analytics and no tracking, and it sends nothing to the developer.
Your settings (including the chess.com username you type in), cached engine evaluations and your training cards are kept in your browser's extension storage. They never leave your device except as described below, and removing the extension deletes them.
api.chess.com): your chess.com username, to list your finished games.lichess.org): chess positions from the opening of a game you review, to fetch evaluations Lichess has already computed. No username or identifier is sent.lichess.org): the game's PGN, only when you click "Lichess" to open the game there.The Stockfish engine runs locally in your browser. These requests follow the privacy policies of Chess.com and Lichess.
On www.chess.com the extension reads the moves and player names of the game shown in your tab, so the side panel can display it. It does not read anything else and does not change the page.
Todor Todorovski, [email protected], todorx.dev.