Stockfish is run in two passes, one fast and one slow. The fast one gets rid of positions unlikely to make good puzzles (only one good move, one side clearly winning, etc.) while the slow one calculates move quality more accurately. Moves are rated relative to the best move in the position, with loss scored in centipawns (1/100th of a pawn). So, losing a pawn for nothing would be ~100 centipawns of loss. Anything over 300 centipawns lost is a blunder, and all blunder moves are scored equally bad.
Each puzzle takes a strong computer ~10 seconds to generate, but I managed to compile about 30,000 for the site. I plan to add more in the future for specific players/tournaments/openings!
aaronpierron•6h ago
I made a site that rates every move in a position with Stockfish (a chess engine, stronger than every human) to give you feedback. Hopefully doing enough of these will reduce the likelihood of catastrophic blunders in real games.
Still a work in progress, and more game modes to come, but hopefully it's fun for any chess players out there. Feel free to ask me questions and I'll reply in the comments.