Free chess analysis means analyzing your games without a subscription, credit cap, or move limit. Chess Masti AI offers fully free chess analysis powered by Stockfish (the world's strongest open-source engine) and Claude AI (which explains the engine output in plain language). Paste a PGN from Lichess, Chess.com, or any other source. The engine runs in your browser. The coach explains every critical move.
Full Stockfish evaluation
Every move evaluated by Stockfish. Centipawn loss, best line, and move classification (inaccuracy, mistake, blunder) for the whole game. Engine runs locally in your browser via WebAssembly — your games stay private.
Natural-language explanations
Claude AI reads the engine output and explains what happened. Not just 'best move is Nf3' but 'the knight protects e5 and prepares a kingside attack while denying Black the d4 break.'
Mistake puzzles
Your worst blunders automatically become drills. Practice the exact positions you keep getting wrong until the pattern sticks.
Follow-up questions
Ask the coach anything about the position. The chat holds context across your whole game so you can dig into the specific moment that confused you.
1. Copy the PGN from Lichess, Chess.com, or your tournament platform. Most sites have an export-PGN button on the game review page.
2. Paste the PGN into Chess Masti's analysis board. The engine starts evaluating immediately. There is no upload step and no server round-trip for the engine work.
3. Click through the moves. At critical moments, the coach explains what happened. Convert any mistake into a puzzle with one tap if you want to drill it later.
Lichess analysis is excellent and free — it's the gold standard for raw engine evaluation. What it does not do is explain anything in plain language. You get the numbers; you have to figure out what they mean yourself.
Chess Masti adds the explanation layer on top of comparable engine accuracy. If you want numbers, Lichess is great. If you want to learn from your games without becoming an engine-output translator, the explanation layer matters.
See how the full free AI chess coach works
The exact-match page covers the engine + AI pipeline in more detail, including how Chess Masti verifies its explanations against Stockfish before showing them to you.
Open the free AI chess coach pageStart your free chess analysis
Paste a PGN. The engine runs in your browser.