chess.com.puter

Free Stockfish analysis in a side panel. Free the fish!

Free the fish! Analyze your chess.com games with Stockfish -- for free, right in a side panel. chess.com.puter brings the power of Stockfish 18 to your browser without paying for a premium subscription. Open any completed game on chess.com, click Import, and get a full game analysis in seconds. FEATURES Full Game Analysis Every position evaluated by Stockfish 18 running locally in your browser. No server. No cloud. No waiting in a queue. Your computer does the work. Move Classifications See exactly where you went wrong (and right). Moves are classified using the Expected Points model: Best, Excellent, Good, Inaccuracy, Mistake, and Blunder -- with colored annotations and icons on the board. Accuracy Score Your overall accuracy percentage, calculated using the same formula as Lichess. Interactive Board Click any move to jump to that position. Drag pieces to explore "what if" lines -- hypothetical variations appear inline in the move list. Evaluation Chart A smoothed win-probability graph over the entire game. Click anywhere on the chart to jump to that moment. Mistakes and blunders are marked with colored dots. Multi-PV Engine Lines See the top 1-5 engine lines updating in real-time as Stockfish searches deeper. Adjust depth and number of lines with simple controls. Best Move Arrows Semi-transparent arrows on the board show what the engine recommends. Player-Focused Summary stats, accuracy, and move coloring focus on your moves. Flip the board to see your opponent's perspective. Open in Lichess One click to continue analysis on lichess.org's full analysis board. ANTI-CHEATING This extension only works on completed games. Stockfish analysis is strictly disabled during active games -- three independent checks enforce this. Games are never auto-imported; you always choose when to analyze. PRIVACY Zero network calls at runtime. No APIs. No tracking. No data collection. Everything runs locally on your machine. The source code is open and auditable. TECHNICAL DETAILS Built with Lichess open-source tools: chessground (board UI), chessops (chess logic), and Stockfish 18 WebAssembly. Vanilla JavaScript -- no frameworks. ~15 MB total (mostly the Stockfish neural network). FREE & OPEN SOURCE Licensed under GPL-3.0. Free as in freedom, free as in beer. Free the fish! https://github.com/reynoldsnlp/chess.com.puter DISCLAIMER Chess.com is a registered trademark of Chess.com, LLC. This extension is an independent, open-source project and is not affiliated with, endorsed by, or sponsored by Chess.com, LLC. Lichess is a registered trademark of Lichess.org. This extension is not affiliated with or endorsed by Lichess.org.