The ECO Index
Every chess opening has a home in the Encyclopaedia of Chess Openings — five volumes, five hundred codes. Explore them all, each with its own complete guide.
ABrowse volume A (333)
Flank & Uncommon Openings
Everything that starts away from the classical centre: the English, Réti, Bird's, plus the Benoni, Benko, Dutch and other fighting defences to 1.d4.
A00Uncommon Opening1.a3…A01Nimzowitsch-Larsen Attack1.b3 e5 2.Bb2 Nc6 3.c4…A02Bird's Opening1.f4 d5 2.Nf3 Nf6 3.e3…A03Bird's Opening, Dutch Variation1.f4 d5 2.Nf3 Nf6 3.e3 g6 4.b3…A04Réti Opening1.Nf3 d5 2.c4 e6 3.g3 Nf6 4.Bg2…A05Réti Opening, 1...Nf61.Nf3 Nf6 2.c4 e6 3.Nc3 d5 4.d4…A06Réti Opening, 1...d51.Nf3 d5 2.c4 e6 3.g3 Nf6 4.Bg2…A07King's Indian Attack1.Nf3 d5 2.g3 Nf6 3.Bg2 e6 4.O-O…A08Réti Opening, King's Indian Attack1.Nf3 d5 2.g3 c5 3.Bg2 Nc6 4.O-O…A09Réti Opening, Accepted Variation1.Nf3 d5 2.c4 dxc4 3.e3 Nf6 4.Bxc4…A10English Opening1.c4 Nf6 2.Nc3 e5 3.Nf3 Nc6 4.g3…A11English Opening, Caro-Kann Defensive System1.c4 c6 2.Nf3 d5 3.b3 Nf6 4.g3…A12English Opening, Réti System1.c4 c6 2.Nf3 d5 3.b3 Nf6 4.g3…A13English Opening, Agincourt Defence1.c4 e6 2.Nc3 d5 3.d4 Nf6 4.Nf3…A14English Opening, Neo-Catalan Declined1.c4 e6 2.Nf3 d5 3.g3 Nf6 4.Bg2…A15English Opening, Anglo-Indian Defence1.c4 Nf6 2.Nf3 g6 3.g3 Bg7 4.Bg2…A16English, Anglo-Indian, Queen's Knight Variation1.c4 Nf6 2.Nc3 e6 3.Nf3 b6 4.e4…A17English Opening, Queen's Indian Setup1.c4 Nf6 2.Nc3 e6 3.Nf3 b6 4.e4…A18English, Mikenas-Carls Variation1.c4 Nf6 2.Nc3 e6 3.e4 c5 4.e5…A19English, Mikenas-Carls, Sicilian Variation1.c4 Nf6 2.Nc3 e6 3.e4 c5 4.e5…A20English Opening, King's English1.c4 e5 2.Nc3 Nf6 3.Nf3 Nc6 4.g3…A21English Opening, King's English, Reversed Sicilian1.c4 e5 2.Nc3 Nf6 3.Nf3 Nc6 4.g3…A22English Opening, Two Knights Variation1.c4 e5 2.Nc3 Nf6 3.Nf3 Nc6 4.e3…A23English, Bremen System, Keres Variation1.c4 e5 2.Nc3 Nf6 3.Nf3 Nc6 4.g3…
+ 76 more codes in volume A
BBrowse volume B (348)
Semi-Open Games
1.e4 against everything except 1...e5: the mighty Sicilian, the fortress Caro-Kann, the hypermodern Pirc & Modern, Alekhine's provocation and the Scandinavian.
B00King's Pawn Opening1.e4…B01Scandinavian Defence1.e4 d5 2.exd5 Qxd5 3.Nc3 Qa5 4.d4…B02Alekhine's Defence1.e4 Nf6 2.e5 Nd5 3.d4 d6 4.Nf3…B03Alekhine's Defence, Four Pawns Attack1.e4 Nf6 2.e5 Nd5 3.d4 d6 4.c4…B04Alekhine's Defence, Modern Variation1.e4 Nf6 2.e5 Nd5 3.d4 d6 4.Nf3…B05Alekhine's, Modern, Main Line1.e4 Nf6 2.e5 Nd5 3.d4 d6 4.Nf3…B06Modern Defence1.e4 g6 2.d4 Bg7 3.Nc3 d6 4.f4…B07Pirc Defence1.e4 d6 2.d4 Nf6 3.Nc3 g6 4.Nf3…B08Pirc, Classical Variation1.e4 d6 2.d4 Nf6 3.Nc3 g6 4.Nf3…B09Pirc, Austrian Attack1.e4 d6 2.d4 Nf6 3.Nc3 g6 4.f4…B10Caro-Kann Defence1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4…B11Caro-Kann, Two Knights Variation1.e4 c6 2.Nc3 d5 3.Nf3 Bg4 4.h3…B12Caro-Kann, Advance Variation1.e4 c6 2.d4 d5 3.e5 Bf5 4.Nf3…B13Caro-Kann, Exchange Variation1.e4 c6 2.d4 d5 3.exd5 cxd5 4.Bd3…B14Caro-Kann, Panov-Botvinnik Attack1.e4 c6 2.d4 d5 3.exd5 cxd5 4.c4…B15Caro-Kann, Main Line 3.Nc31.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4…B16Caro-Kann, Bronstein-Larsen Variation1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4…B17Caro-Kann, Steinitz Variation1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4…B18Caro-Kann, Classical Variation1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4…B19Caro-Kann, Classical, 7...Nd7 Main1.e4 c6 2.d4 d5 3.Nc3 dxe4 4.Nxe4…B20Sicilian Defence1.e4 c5…B21Sicilian, Smith-Morra Gambit1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3…B22Sicilian, Alapin Variation1.e4 c5 2.c3 Nf6 3.e5 Nd5 4.d4…B23Sicilian, Closed Variation1.e4 c5 2.Nc3 Nc6 3.g3 g6 4.Bg2…
+ 76 more codes in volume B
CBrowse volume C (335)
Open Games & the French
The oldest battlegrounds in chess — the Ruy Lopez, Italian Game, Scotch and King's Gambit — plus the entire French Defence complex.
C00French Defence1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.e5…C01French, Exchange Variation1.e4 e6 2.d4 d5 3.exd5 exd5 4.Nf3…C02French, Advance Variation1.e4 e6 2.d4 d5 3.e5 c5 4.c3…C03French, Tarrasch Variation1.e4 e6 2.d4 d5 3.Nd2 Nf6 4.e5…C04French, Tarrasch, Guimard Main Line1.e4 e6 2.d4 d5 3.Nd2 Nc6 4.Ngf3…C05French, Tarrasch, Closed Variation1.e4 e6 2.d4 d5 3.Nd2 Nf6 4.e5…C06French, Tarrasch, Main Line1.e4 e6 2.d4 d5 3.Nd2 Nf6 4.e5…C07French, Tarrasch, Open Variation1.e4 e6 2.d4 d5 3.Nd2 c5 4.exd5…C08French, Tarrasch, Open, 4.exd5 exd51.e4 e6 2.d4 d5 3.Nd2 c5 4.exd5…C09French, Tarrasch, Open, Main Line1.e4 e6 2.d4 d5 3.Nd2 c5 4.exd5…C10French, Paulsen Variation1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.e5…C11French, Classical Variation1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.e5…C12French, MacCutcheon Variation1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.Bg5…C13French, Classical, 4.Bg5 Be71.e4 e6 2.d4 d5 3.Nc3 Nf6 4.Bg5…C14French, Classical, Main Line1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.Bg5…C15French, Winawer Variation1.e4 e6 2.d4 d5 3.Nc3 Bb4 4.e5…C16French, Winawer, Advance Variation1.e4 e6 2.d4 d5 3.Nc3 Bb4 4.e5…C17French, Winawer, Advance, 4...Qa51.e4 e6 2.d4 d5 3.Nc3 Bb4 4.e5…C18French, Winawer, Advance, Classical1.e4 e6 2.d4 d5 3.Nc3 Bb4 4.e5…C19French, Winawer, Poisoned Pawn1.e4 e6 2.d4 d5 3.Nc3 Bb4 4.e5…C20King's Pawn Game1.e4 e5 2.Nf3…C21Centre Game1.e4 e5 2.d4 exd4 3.Qxd4 Nc6 4.Qe3…C22Centre Game, Normal Variation1.e4 e5 2.d4 exd4 3.Qxd4 Nc6 4.Qe3…C23Bishop's Opening1.e4 e5 2.Bc4 Nf6 3.d3 c6 4.Bb3…
+ 76 more codes in volume C
DBrowse volume D (249)
Closed & Semi-Closed Games
The land of 1.d4 d5: the Queen's Gambit complex, the steel of the Slav, the classical QGD and the dynamic Grünfeld Defence.
D00Queen's Pawn Game1.d4 d5 2.e4…D01Richter-Veresov Attack1.d4 d5 2.Nc3 Nf6 3.Bg5 Bf5 4.f3…D02Queen's Pawn Game, 2.Nf31.d4 d5 2.Nf3 Nf6 3.Bf4 e6 4.e3…D03Torre Attack (Tartakower Variation)1.d4 d5 2.Nf3 Nf6 3.Bg5 e6 4.e3…D04Queen's Pawn Game, Colle Setup1.d4 d5 2.Nf3 Nf6 3.e3 c5 4.c3…D05Colle System1.d4 d5 2.Nf3 Nf6 3.e3 e6 4.Bd3…D06Queen's Gambit1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.Nf3…D07Queen's Gambit, Chigorin Defence1.d4 d5 2.c4 Nc6 3.Nf3 Bg4 4.cxd5…D08Queen's Gambit, Albin Counter-Gambit1.d4 d5 2.c4 e5 3.dxe5 d4…D09Albin Counter-Gambit, 5.g3 Main1.d4 d5 2.c4 e5 3.dxe5 d4 4.Nf3…D10Slav Defence1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3…D11Slav Defence, Quiet Variation1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.e3…D12Slav, Quiet, 4.e3 Bf51.d4 d5 2.c4 c6 3.Nf3 Nf6 4.e3…D13Slav, Main Line1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3…D14Slav, Exchange Variation1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.cxd5…D15Slav, Three Knights Variation1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3…D16Slav, Alapin Variation1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3…D17Slav, Czech Variation1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3…D18Slav, Dutch Variation1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3…D19Slav, Czech, Main Line1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3…D20Queen's Gambit Accepted1.d4 d5 2.c4 dxc4 3.Nf3 Nf6 4.e3…D21Queen's Gambit Accepted, 3.Nf31.d4 d5 2.c4 dxc4 3.Nf3 Nf6 4.e3…D22QGA, Alekhine Defence1.d4 d5 2.c4 dxc4 3.Nf3 a6 4.e3…D23QGA, Old Variation1.d4 d5 2.c4 dxc4 3.Nf3 Nf6 4.Qc2…
+ 76 more codes in volume D
EBrowse volume E (241)
Indian Defences
The great Indian complex: the Nimzo-Indian and Queen's Indian, the King's Indian's all-out counterattacks, and the elegant Catalan.
E00Catalan Opening1.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2…E01Catalan, Closed Variation1.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2…E02Catalan, Open, Classical Line1.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2…E03Catalan, Open, Alekhine Variation1.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2…E04Catalan, Open, 5.Nf3 Main1.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2…E05Catalan, Open, Classical Main Line1.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2…E06Catalan, Closed, 5.Nf31.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2…E07Catalan, Closed, 6.Qc21.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2…E08Catalan, Closed, Main Line1.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2…E09Catalan, Closed, Main Line with 9...b51.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2…E10Queen's Indian Defence1.d4 Nf6 2.c4 e6 3.Nf3 b6 4.Nc3…E11Bogo-Indian Defence1.d4 Nf6 2.c4 e6 3.Nf3 Bb4+ 4.Bd2…E12Queen's Indian, Petrosian Variation1.d4 Nf6 2.c4 e6 3.Nf3 b6 4.a3…E13Queen's Indian, 4.Nc31.d4 Nf6 2.c4 e6 3.Nf3 b6 4.Nc3…E14Queen's Indian, 4.e31.d4 Nf6 2.c4 e6 3.Nf3 b6 4.e3…E15Queen's Indian, Fianchetto Variation1.d4 Nf6 2.c4 e6 3.Nf3 b6 4.g3…E16Queen's Indian, Capablanca Variation1.d4 Nf6 2.c4 e6 3.Nf3 b6 4.g3…E17Queen's Indian, 5.Bg2 Be71.d4 Nf6 2.c4 e6 3.Nf3 b6 4.g3…E18Queen's Indian, Old Main Line1.d4 Nf6 2.c4 e6 3.Nf3 b6 4.g3…E19Queen's Indian, Classical Main Line1.d4 Nf6 2.c4 e6 3.Nf3 b6 4.g3…E20Nimzo-Indian Defence1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3…E21Nimzo-Indian, Three Knights Variation1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.Nf3…E22Nimzo-Indian, Spielmann Variation1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.Qc2…E23Nimzo-Indian, Spielmann, 4...c5 5.dxc51.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.Qc2…
+ 76 more codes in volume E