Decode Chess is an analysis tool that addresses a common frustration with engine analysis: the engine shows the best move but gives no explanation of why it is best. Decode Chess adds natural language explanations to engine evaluations, translating the computer's suggested moves into human-readable descriptions of the strategic and tactical ideas behind them.

Users upload a game in PGN format and Decode Chess analyzes it move by move, generating a report that includes both the numerical evaluation and explanatory text — such as "White should play Nd5 to exploit the outpost and create a threat against the bishop on e7" rather than just showing the move with a centipawn score.

Decode Chess offers one free analysis per day; additional analyses require a subscription. It is particularly valuable for intermediate players who want to learn from their games but find pure engine output difficult to turn into useful lessons.