Game analysis shows where you lost ground and what you should have played. Stockfish 18 goes through every position, compares the move played with its own best move, and turns the difference into move labels and accuracy. The game can come from Chess.com, Lichess or a PGN.
What the analysis shows
Every move gets a label, from Brilliant to Blunder, and an evaluation before and after it. The losses across all moves add up to each side’s accuracy, with the same formula Lichess uses. The evaluation graph draws the game as one curve, and a sharp swing on it usually lines up with a blunder or a missed tactic.
The best move in every position
Under a mistake you see the move the engine preferred and its line. The gap between the evaluations is the cost of the mistake in pawns. You can play the engine line out on the board, or play your own line and let the engine evaluate the new position.
Analyze a game in three steps
- Import the game. A Chess.com or Lichess username pulls recent games; a PGN can be pasted as text or uploaded as a file.
- Open it. Stockfish searches in your browser to depth 15 and takes known positions straight from the evaluation database.
- Start with the sharp swings on the graph. At each one, look at the best move and find the idea you missed.
Where to go next
- Free Chess Analysis: how many games you can analyze and how it compares with Chess.com.
- Chess Review: reviewing a series of games after a session.
- FEN Analyzer: one position instead of a whole game.
- PGN Analyzer: games from PGN files.