ECO index: A00--A99

A00: Uncommon Openings: 1. g3 (Benko Opening), 1. Nc3 (Sleipner Opening), 1. a3 (Anderssen's Opening), 1. b4 (Polish Opening), 1. g4 (Grob's Attack), 1. h3 (Basmanic Defence), 1. c3 (Saragossa Opening), 1. d3 (Mieses Opening), 1. e3 (French Attack), 1. h4 (Desprez Opening), 1. a4 (Ware Opening), 1. Nh3 (Amar Opening), 1. Na3 (Durkin's Attack), 1. f3 (Gedult's Opening), 1. e3 e5 2. e4 (King's Isa Reverse)

A01: Nimzowitsch-Larsen Attack: 1. b3

A02: Bird's Opening: 1. f4

A03: Bird's Opening: 1. f4 d5

A04: Reti Opening: 1. Nf3

A05: Reti Opening: 1. Nf3 Nf6

A06: Reti Opening: 1. Nf3 d5

A07: King's Indian Attack: 1. Nf3 d5 2. g3

A08: King's Indian Attack: 1. Nf3 d5 2. g3 c5 3. Bg2

A09: Reti Opening: 1. Nf3 d5 2. c4

A10: English: 1. c4

A11: English, Anglo-Slav System: 1. c4 c6

A12: English with b3: 1. c4 c6 2. Nf3 d5 3. b3

A13: English: 1. c4 e6

A14: English: 1. c4 e6 2. Nf3 d5 3. g3 Nf6 4. Bg2 Be7 5. O-O

A15: English: 1. c4 Nf6

A16: English: 1. c4 Nf6 2. Nc3

A17: English: 1. c4 Nf6 2. Nc3 e6

A18: English, Mikenas-Carls: 1. c4 Nf6 2. Nc3 e6 3. e4

A19: English, Mikenas-Carls, Sicilian Variation: 1. c4 Nf6 2. Nc3 e6 3. e4 c5

A20: English: 1. c4 e5

A21: English: 1. c4 e5 2. Nc3

A22: English: 1. c4 e5 2. Nc3 Nf6

A23: English, Bremen System, Keres Variation: 1. c4 e5 2. Nc3 Nf6 3. g3 c6

A24: English, Bremen System with ...g6: 1. c4 e5 2. Nc3 Nf6 3. g3 g6

A25: English: 1. c4 e5 2. Nc3 Nc6

A26: English: 1. c4 e5 2. Nc3 Nc6 3. g3 g6 4. Bg2 Bg7 5. d3 d6

A27: English, Three Knights System: 1. c4 e5 2. Nc3 Nc6 3. Nf3

A28: English: 1. c4 e5 2. Nc3 Nc6 3. Nf3 Nf6

A29: English, Four Knights, Kingside Fianchetto: 1. c4 e5 2. Nc3 Nc6 3. Nf3 Nf6 g3

A30: English, Symmetrical: 1. c4 c5

A31: English, Symmetrical, Benoni Formation: 1. c4 c5 2. Nf3 Nf6 3. d4

A32: English, Symmetrical Variation: 1. c4 c5 2. Nf3 Nf6 3. d4 cxd4 4. Nxd4 e6

A33: English, Symmetrical: 1. c4 c5 2. Nf3 Nf6 3. d4 cxd4 4. Nxd4 e6 5. Nc3 Nc6

A34: English, Symmetrical: 1. c4 c5 2. Nc3

A35: English, Symmetrical: 1. c4 c5 2. Nc3 Nc6

A36: English, Symmetrical: 1. c4 c5 2. Nc3 Nc6 3. g3 g6 4. Bg2 Bg7

A37: English, Symmetrical: 1. c4 c5 2. Nc3 Nc6 3. g3 g6 4. Bg2 Bg7 5. Nf3

A38: English, Symmetrical: 1. c4 c5 2. Nc3 Nc6 3. g3 g6 4. Bg2 Bg7 5. Nf3 Nf6

A39: English, Symmetrical: 1. c4 c5 2. Nc3 Nc6 3. g3 g6 4. Bg2 Bg7 5. Nf3 Nf6 6. O-O O-O 7. d4

A40: Unusual Black responses to 1. d4: 1...e5 (Englund Gambit), 1...b5 (Polish Defence), 1...Nc6 (Nimzowitsch Defence), 1...g6 (Modern Defence without 2. e4), 1...e6 (French Indian Defence).

A41: Tartakower System: 1. d4 d6

A42: Tartakower System with 2. c4: 1. d4 d6 2.c4

A43: Various Benonis: 1. d4 c5

A44: Old Benoni: 1. d4 c5 2. d5 e5

A44: Semi-Benoni: 1. d4 c5 2. d5 e5 3. e4 d6

A45: Unusual Indian Openings: 1. d4 Nf6

A45: Trompowsky Attack: 1. d4 Nf6 2. Bg5

A46: Unusual Indian Openings with 2. Nf3: 1. d4 Nf6 2. Nf3

A47: Unusual Indian Openings with 2. Nf3: 1. d4 Nf6 2. Nf3 b6

A48: Torre Attack with 2...e6: 1. d4 Nf6 2. Nf3 e6 3. Bg5

A48: Torre Attack with 2...g6: 1. d4 Nf6 2. Nf3 g6 3. Bg5

A48: London System: 1. d4 Nf6 2. Nf3 e6 3. Bf4

A49: Fianchetto Variation: 1. d4 Nf6 2. Nf3 e6 3. g3

A50: Black Knights' Tango: 1. d4 Nf6 2. c4 Nc6

A51: Budapest Gambit Declined and Unusual Lines: 1. d4 Nf6 2. c4 e5

A52: Budapest Gambit Main Lines: 1. d4 Nf6 2. c4 e5 3. dxe5 Ng4

A53: Old Indian Defence: 1. d4 Nf6 2. c4 d6

A54: Old Indian Defence main lines: 1. d4 Nf6 2. c4 d6 3. Nc3 e5

A55: Old Indian Defence main lines: 1. d4 Nf6 2. c4 d6 3. Nc3 e5 4. Nf3

A56: Czech Benoni: 1. d4 Nf6 2. c4 c5 3. d5

A57: Benko/Volga Gambit sidelines: 1. d4 Nf6 2. c4 c5 3. d5 b5

A58: Benko/Volga Gambit Accepted: 1. d4 Nf6 2. c4 c5 3. d5 b5 4. cxb5

A59: Benko/Volga Gambit Accepted (White castles by hand): 1. d4 Nf6 2. c4 c5 3. d5 b5 4. cxb5 a6 5. bxa6 Bxa6 6. Nc3 d6 7. e4

A60: Modern Benoni and early divergences: 1. d4 Nf6 2. c4 c5 3. d5 e6

A61: Modern Benoni without early e4: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6

A62: Modern Benoni, Fianchetto Variation without early ...Nbd7: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. Nf3 g6 7. g3

A63: Modern Benoni, Fianchetto Variation sidelines: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. Nf3 g6 7. g3 Bg7 8. Bg2 O-O

A64: Modern Benoni, Fianchetto Variation main line: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. Nf3 g6 7. g3 Bg7 8. Bg2 O-O 9. O-O Re8 10. Nd2 Nbd7

A65: Modern Benoni, sidelines with early e4: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4

A66: Modern Benoni, Mikenas Attack: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. f4 Bg7 8. e5

A67: Modern Benoni, Taimanov Variation: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. f4 Bg7 8. Bb5+

A68: Modern Benoni, Four Pawns Attack without 9...Re8: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. f4 Bg7 8. Nf3 O-O 9. Bd3

A69: Modern Benoni, Four Pawns Attack with 9...Re8: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. f4 Bg7 8. Nf3 O-O 9. Re8

A70: Modern Benoni, 7.Nf3: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Nf3

A71: Modern Benoni, 7.Nf3 Bg7 8.Bg5 without Be2: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Nf3 Bg7 8. Bg5

A72: Modern Benoni, Classical Variation with Bg5: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Nf3 Bg7 8. Be2 O-O 9. Bg5

A73: Modern Benoni, Classical Variation and unusual Black 9th moves: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Nf3 Bg7 8. Be2 O-O 9. O-O

A74: Modern Benoni, Classical Variation with 9...a6: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Nf3 Bg7 8. Be2 O-O 9. O-O a6

A75: Modern Benoni, Classical Variation main line: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Nf3 Bg7 8. Be2 O-O 9. O-O a6 10. a4 Bg4

A76: Modern Benoni, Classical Variation with 9...Re8 10.Qc2: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Nf3 Bg7 8. Be2 O-O 9. O-O Re8 10. Qc2

A77: Modern Benoni, Classical Variation with 9...Re8 10.Nd2: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Nf3 Bg7 8. Be2 O-O 9. O-O Re8 10. Nd2

A78: Modern Benoni, Classical Variation with 10...Na6: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Nf3 Bg7 8. Be2 O-O 9. O-O Re8 10. Nd2 Na6

A79: Modern Benoni, Classical Variation with 10...Na6 11.f3: 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Nf3 Bg7 8. Be2 O-O 9. O-O Re8 10. Nd2 Na6 11. f3

A80: Dutch Defence and unusual White second moves: 1. d4 f5

A81: Dutch Defence with 2.g3: 1. d4 f5 2. g3

A82: Dutch Defence, Staunton Gambit: 1. d4 f5 2. e4

A83: Dutch Defence, Staunton Gambit with 3.Nc3 Nf6 4.Bg5: 1. d4 f5 2. e4 fxe4 3. Nc3 Nf6 4. Bg5

A84: Dutch Defence, 2.c4: 1. d4 f5 2. c4

A85: Dutch Defence, 2.c4 Nf6 3.Nc3: 1. d4 f5 2. c4 Nf6 3. Nc3

A86: Dutch Defence, Leningrad Variation sidelines: 1. d4 f5 2. c4 Nf6 3. g3

A87: Dutch Defence, Leningrad Variation with 5.Nf3: 1. d4 f5 2. c4 Nf6 3. g3 g6 4. Bg2 Bg7 5. Nf3

A88: Dutch Defence, Leningrad Variation main line 7...c6: 1. d4 f5 2. c4 Nf6 3. g3 g6 4. Bg2 Bg7 5. Nf3 O-O 6. O-O d6 7. Nc3 c6

A89: Dutch Defence, Leningrad Variation main line 7...Nc6: 1. d4 f5 2. c4 Nf6 3. g3 g6 4. Bg2 Bg7 5. Nf3 O-O 6. O-O d6 7. Nc3 Nc6

A90: Dutch Defence sidelines and Stonewall: 1. d4 f5 2. c4 Nf6 3. g3 e6

A91: Dutch Defence, Classical Variation sidelines: 1. d4 f5 2. c4 Nf6 3. g3 e6 4. Bg2 Be7

A92: Dutch Defence, Classical Stonewall with ...Be7 and early deviations: 1. d4 f5 2. c4 Nf6 3. g3 e6 4. Bg2 Be7 5. Nf3

A93: Dutch Defence, Classical Stonewall with 7.b3: 1. d4 f5 2. c4 Nf6 3. g3 e6 4. Bg2 Be7 5. Nf3 d5 6. O-O O-O 7. b3

A94: Dutch Defence, Classical Stonewall with 7.b3 c6 8.Ba3: 1. d4 f5 2. c4 Nf6 3. g3 e6 4. Bg2 Be7 5. Nf3 d5 6. O-O O-O 7. b3 c6 8. Ba3

A95: Dutch Defence, Classical Stonewall with 7.Nc3 c6: 1. d4 f5 2. c4 Nf6 3. g3 e6 4. Bg2 Be7 5. Nf3 d5 6. O-O O-O 7. Nc3 c6

A96: Dutch Defence, Ilyin-Genevsky Variation: 1. d4 f5 2. c4 Nf6 3. g3 e6 4. Bg2 Be7 5. Nf3 O-O 6. O-O d6

A97: Dutch Defence, Ilyin-Genevsky Variation: 1. d4 f5 2. c4 Nf6 3. g3 e6 4. Bg2 Be7 5. Nf3 O-O 6. O-O d6 7. Nc3 Qe8

A98: Dutch Defence, Ilyin-Genevsky Variation with 8.Qc2: 1. d4 f5 2. c4 Nf6 3. g3 e6 4. Bg2 Be7 5. Nf3 O-O 6. O-O d6 7. Nc3 Qe8 8. Qc2

A99: Dutch Defence, Ilyin-Genevsky Variation with 8.b3: 1. d4 f5 2. c4 Nf6 3. g3 e6 4. Bg2 Be7 5. Nf3 O-O 6. O-O d6 7. Nc3 Qe8 8. b3

ECO volumes

External Links

Chess Archaeology: Openings classified ECO A00-A99 from chessarch.com