How to Analyze Chess Games with Stockfish (Any Game, Free)

A complete, platform-agnostic guide to running a Stockfish analysis on any chess game — Chess.com, Lichess, over-the-board, or a plain PGN file.

Stockfish is free, open source, and the strongest publicly available chess engine. The confusing part for most players is not the engine itself — it is figuring out how to actually point it at your game, whatever site or app that game came from. This guide covers every path, whether you played on Chess.com, Lichess, a different app entirely, or across the board at a club.

You do not need to install anything

Stockfish is a command-line engine with no interface of its own, which is why most players never touch it directly. In practice you have two options: a desktop chess GUI that runs Stockfish locally, or a web tool that runs Stockfish on a server (or in your browser) and shows you the result. For a one-off game, the web route is faster and needs zero setup.

Step 1: Get the game into a movable format

Every method below needs the same starting point: the game as a PGN, the universal text format for a recorded game. Chess.com and Lichess both let you export or share a PGN directly. For an over-the-board game, your scoresheet moves typed out as plain algebraic notation (1. e4 e5 2. Nf3 …) already qualify. See our full breakdown of the PGN format if you want to understand the syntax, or how to import a PGN for analysis for the mechanics of loading one into a tool.

Step 2: Run the engine

Once the game is loaded into an analysis tool, Stockfish evaluates every position from the game and assigns a score to each move — effectively a running commentary on how good or bad each decision was. A moderate search depth is enough to catch every real blunder in a club-level game; you rarely need maximum depth unless you are settling a genuinely sharp tactical dispute.

Step 3: Read what the engine gives you back

A useful Stockfish report boils down to three things:

• An evaluation graph — the shape of the whole game at a glance. Sharp drops mark the moments that actually decided the result.
• Move classifications — Best, Good, Inaccuracy, Mistake, Blunder on every move, so you do not have to read the raw evaluation number yourself. See our guide to what these labels mean.
• The best line at any position you click, so you can see not just what you should have played but where it led.

Chess.com, Lichess, or neither — does it matter?

Not to the engine. Stockfish evaluates a chess position, not a website. The only thing that changes between platforms is how you get the moves out. If your games live on Chess.com specifically, our Chess.com-specific walkthrough covers the exact export steps. Lichess games export just as easily from any game page. A game that only exists on a scoresheet or in a different app works too, the moment you have it as text.

Local engine vs. web tool

Serious correspondence players and coaches sometimes run Stockfish locally through a desktop GUI, which allows unlimited depth and multi-hour analysis of a single position. For reviewing your own games after a session, that is overkill: a web tool that runs the same engine on a server gives you a full-game report in under a minute, with nothing to configure. Use a local install only if you need to analyze one critical position far deeper than a casual review requires.

Turning the analysis into improvement

A report full of labels is only the first half. The habit that actually moves your rating is going back to your Mistakes and Blunders, setting up the position, and finding the better move yourself before revealing the engine’s answer. Our step-by-step game review process covers exactly how to structure that.

Chesslume runs every game you import — from Chess.com, Lichess, or a pasted PGN — through Stockfish 18 with NNUE, free and unlimited, and turns the mistakes it finds into puzzles built from your own positions.