Chessigma answers chess questions with its opening guides, an opening catalogue and facts computed from the rules of chess. Ask about the London, the Caro-Kann, the Sicilian and 15 more openings to get the main line, the key variations and the ideas for both sides from Chessigma's opening guides, or name any of 3,700 catalogued lines to get its ECO code and moves. Paste moves to identify an opening and see where a game left theory. Paste a FEN to get the side to move, check or mate status, material and every legal move. Paste a PGN to get a summary (players, result, opening, how the game ended) and a link that opens the game on the chessigma.com analysis board, plus a review link when the PGN comes from a Chess.com live game or a Lichess game. Share a Chess.com live game link or a Lichess game link to get a link to that game's full move-by-move review on chessigma.com. On those pages Stockfish runs in your own browser. Also: the daily puzzle with its solution, and Elo estimates with FIDE, Chess.com or Lichess K-factor defaults (Chess.com and Lichess use Glicko ratings, so their real changes differ). No account needed.
For chess players of any level who want facts about openings, positions and games. Chessigma does not evaluate positions inside ChatGPT, does not play games, and cannot read your Chess.com or Lichess account: share a game link or a PGN instead.