Guide · Updated August 2026
How to use Stockfish to analyze your games
By Audit ChessTo use Stockfish, load a position or game and read its evaluation in pawns - positive favours White, negative favours Black, a mate score means forced mate. Analyze move by move, but form your own plan before checking the engine, and treat its lines as a check, not a script.
What Stockfish is and how to run it
Stockfish is the strongest open-source chess engine. You do not need to install anything to use it - it runs directly in the browser on Lichess, in the Chess.com analysis board, and in tools like Audit Chess, where it is compiled to WebAssembly and analyses your game on your own device. Paste a game's PGN or step through a position and the engine evaluates each move.
For most improving players, an in-browser Stockfish is more than strong enough. You get a top move, a principal variation (the engine's expected line), and an evaluation for every position.
Reading the evaluation
The evaluation is shown in pawns. +1.5 means White is about a pawn and a half better; -0.8 means Black is slightly better; a score like #4 means a forced mate in four. Zero, or close to it, means the position is balanced. The number assumes best play from both sides, so it describes potential, not a guaranteed result.
What matters most is the change in evaluation between your move and the engine's best move. A big drop in your favourite direction is where you went wrong - that is how the engine turns a game into a list of your mistakes.
Analyze move by move - but think first
The mistake most players make with Stockfish is turning on the engine and passively reading the answers. You learn far more by pausing at each critical position, deciding what you would play and why, and only then checking the engine. If it disagrees, you have found a real gap in your understanding - which is the whole point.
When the engine flags a mistake, do not just note the better move. Ask why your move was worse and what pattern would have warned you. The explanation is the lesson; the move is just the answer.
Know the engine's limits
Stockfish tells you the best move, but not always why, and not what is realistic for a human to play. Some engine lines require a precise ten-move sequence no club player would find over the board. Use the engine to catch your blunders and confirm your ideas, but build your understanding from principles and plans, not from memorising machine variations.
The engine is also only as useful as the questions you bring to it. Analysing your whole game history to find the patterns - then using the engine to understand the key moments - beats running the engine blindly over one game at a time.
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Frequently asked questions
How do I analyze my chess games with Stockfish?+
Load the game into a Stockfish-powered board - on Lichess, Chess.com, or a tool like Audit Chess where you paste the PGN - and step through it move by move. Read the evaluation change at each move to find your mistakes, and try to work out the best move yourself before revealing the engine's.
What do the Stockfish numbers mean?+
They are the evaluation in pawns: positive favours White, negative favours Black, and a score like #3 means forced mate in three. Zero is balanced. The value assumes best play from both sides.
Is it enough to just follow Stockfish's moves?+
No. Passively reading engine moves teaches you little. Decide your own move first, then check the engine, and focus on understanding why its move is better - the reasoning transfers to your games, the memorised line does not.