Openings
What does ECO mean in chess?
- Opening
- Plans
- Move Order
In chess, ECO refers to the Encyclopaedia of Chess Openings (ECO), a standard and comprehensive chess opening reference. Also ECO code, a classification system for openings that assigns an alphanumeric code from A00 to E99 to each opening.
ECO FAQ
What does ECO mean in chess?
In chess, ECO refers to the Encyclopaedia of Chess Openings (ECO), a standard and comprehensive chess opening reference. Also ECO code, a classification system for openings that assigns an alphanumeric code from A00 to E99 to each opening.
Train this pattern on your own games
Reading a definition is not the same as spotting the pattern with a clock running. Chessiro's free PGN analysis runs Stockfish 19 over every move you play, names the concept behind each mistake, and turns the positions where it cost you into training puzzles. You can also see the idea in action in the classic games collection, where the greatest players in history demonstrate it.
Related terms
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See where this pattern decides your games
Chessiro reviews your games with an AI coach that names the concept behind every mistake, then drills you on the exact positions where it happened until you stop repeating them.
