| Eco | Name | First moves | # games |
|---|
| B22 | Sicilian, Alapin | 1 e4 c5 2 c3 | 8 |
| B01 | Scandinavian | 1 e4 d5 | 7 |
| D00 | Queen's Pawn Game | 1 d4 d5 | 7 |
| D02 | Queen's Pawn Game | 1 d4 d5 2 Nf3 | 7 |
| D11 | Queen's Gambit Declined Slav | 1 d4 d5 2 c4 c6 3 Nf3 | 7 |
| B33 | Sicilian | 1 e4 c5 2 Nf3 Nc6 3 d4 cxd4 4 Nxd4 | 6 |
| C44 | King's Pawn Game | 1 e4 e5 2 Nf3 Nc6 | 6 |
| D36 | Queen's Gambit Declined, Exchange, Positional line, 6.Qc2 | 1 d4 d5 2 c4 e6 3 Nc3 Nf6 4 cxd5 exd5 5 Bg5 c6 6 Qc2 | 6 |
| A00 | Uncommon Opening | 1 a3, b3, d3, g4, etc. | 5 |
| A40 | Queen's Pawn Game | 1 d4 | 5 |
| A05 | Reti Opening | 1 Nf3 Nf6 | 4 |
| A41 | Queen's Pawn Game (with ...d6) | 1 d4 d6 | 4 |
| B10 | Caro-Kann | 1 e4 c6 | 4 |
| B12 | Caro-Kann Defense | 1 e4 c6 2 d4 | 4 |
| B17 | Caro-Kann, Steinitz Variation | 1 e4 c6 2 d4 d5 3 Nc3 dxe4 4 Nxe4 Nd7 | 4 |
| B40 | Sicilian | 1 e4 c5 2 Nf3 e6 | 4 |
| C41 | Philidor Defense | 1 e4 e5 2 Nf3 d6 | 4 |
| D12 | Queen's Gambit Declined Slav | 1 d4 d5 2 c4 c6 3 Nf3 Nf6 4 e3 Bf5 | 4 |
| D52 | Queen's Gambit Declined | 1 d4 d5 2 c4 e6 3 Nc3 Nf6 4 Bg5 Nbd7 5 e3 c6 6 Nf3 | 4 |
| A31 | English, Symmetrical, Benoni Formation | 1 c4 c5 2 Nf3 Nf6 3 d4 | 3 |
| A45 | Queen's Pawn Game | 1 d4 Nf6 | 3 |
| A46 | Queen's Pawn Game | 1 d4 Nf6 2 Nf3 | 3 |
| A49 | King's Indian, Fianchetto without c4 | 1 d4 Nf6 2 Nf3 g6 3 g3 | 3 |
| B07 | Pirc | 1 e4 d6 2 d4 Nf6 | 3 |
| B19 | Caro-Kann, Classical | 1 e4 c6 2 d4 d5 3 Nc3 dxe4 4 Nxe4 Bf5 5 Ng3 Bg6 6 h4 h6 7 Nf3 Nd7 | 3 |
| C30 | King's Gambit Declined | 1 e4 e5 2 f4 | 3 |
| C50 | Giuoco Piano | 1 e4 e5 2 Nf3 Nc6 3 Bc4 Bc5 | 3 |
| D03 | Torre Attack (Tartakower Variation) | 1 d4 d5 2 Nf3 Nf6 3 Bg5 | 3 |
| D06 | Queen's Gambit Declined | 1 d4 d5 2 c4 | 3 |
| D13 | Queen's Gambit Declined Slav, Exchange Variation | 1 d4 d5 2 c4 c6 3 Nf3 Nf6 4 cxd5 cxd5 | 3 |
| E11 | Bogo-Indian Defense | 1 d4 Nf6 2 c4 e6 3 Nf3 Bb4+ | 3 |
| A03 | Bird's Opening | 1 f4 d5 | 2 |
| A04 | Reti Opening | 1 Nf3 | 2 |
| A07 | King's Indian Attack | 1 Nf3 d5 2 g3 | 2 |
| A10 | English | 1 c4 | 2 |
| A12 | English with b3 | 1 c4 c6 2 Nf3 d5 3 b3 | 2 |
| A17 | English | 1 c4 Nf6 2 Nc3 e6 | 2 |
| A26 | English | 1 c4 e5 2 Nc3 Nc6 3 g3 g6 4 Bg2 Bg7 5 d3 d6 | 2 |
| A36 | English | 1 c4 c5 2 Nc3 Nc6 3 g3 | 2 |
| A38 | English, Symmetrical | 1 c4 c5 2 Nc3 Nc6 3 g3 g6 4 Bg2 Bg7 5 Nf3 Nf6 | 2 |
| A47 | Queen's Indian | 1 d4 Nf6 2 Nf3 b6 | 2 |
| A53 | Old Indian | 1 d4 Nf6 2 c4 d6 | 2 |
| A87 | Dutch, Leningrad, Main Variation | 1 d4 f5 2 c4 Nf6 3 g3 g6 4 Bg2 Bg7 5 Nf3 | 2 |
| B00 | Uncommon King's Pawn Opening | 1 e4 | 2 |
| B02 | Alekhine's Defense | 1 e4 Nf6 | 2 |
| B06 | Robatsch | 1 e4 g6 | 2 |
| B11 | Caro-Kann, Two Knights, 3...Bg4 | 1 e4 c6 2 Nc3 d5 3 Nf3 Bg4 | 2 |
| B27 | Sicilian | 1 e4 c5 2 Nf3 | 2 |
| B29 | Sicilian, Nimzovich-Rubinstein | 1 e4 c5 2 Nf3 Nf6 | 2 |
| B38 | Sicilian, Accelerated Fianchetto, Maroczy Bind, 6.Be3 | 1 e4 c5 2 Nf3 Nc6 3 d4 cxd4 4 Nxd4 g6 5 c4 Bg7 6 Be3 | 2 |
| B51 | Sicilian, Canal-Sokolsky (Rossolimo) Attack | 1 e4 c5 2 Nf3 d6 3 Bb5+ | 2 |
| B53 | Sicilian | 1 e4 c5 2 Nf3 d6 3 d4 cxd4 4 Qxd4 | 2 |
| B76 | Sicilian, Dragon, Yugoslav Attack | 1 e4 c5 2 Nf3 d6 3 d4 cxd4 4 Nxd4 Nf6 5 Nc3 g6 6 Be3 Bg7 7 f3 O-O | 2 |
| C00 | French Defense | 1 e4 e6 | 2 |
| C10 | French | 1 e4 e6 2 d4 d5 3 Nc3 | 2 |
| C55 | Two Knights Defense | 1 e4 e5 2 Nf3 Nc6 3 Bc4 Nf6 | 2 |
| C62 | Ruy Lopez, Old Steinitz Defense | 1 e4 e5 2 Nf3 Nc6 3 Bb5 d6 | 2 |
| C68 | Ruy Lopez, Exchange | 1 e4 e5 2 Nf3 Nc6 3 Bb5 a6 4 Bxc6 | 2 |
| C77 | Ruy Lopez | 1 e4 e5 2 Nf3 Nc6 3 Bb5 a6 4 Ba4 Nf6 | 2 |
| D07 | Queen's Gambit Declined, Chigorin Defense | 1 d4 d5 2 c4 Nc6 | 2 |
| D27 | Queen's Gambit Accepted, Classical | 1 d4 d5 2 c4 dxc4 3 Nf3 Nf6 4 e3 e6 5 Bxc4 c5 6 O-O a6 | 2 |
| D85 | Grunfeld | 1 d4 Nf6 2 c4 g6 3 Nc3 d5 4 cxd5 Nxd5 | 2 |
| E17 | Queen's Indian | 1 d4 Nf6 2 c4 e6 3 Nf3 b6 4 g3 Bb7 5 Bg2 Be7 | 2 |
| E32 | Nimzo-Indian, Classical | 1 d4 Nf6 2 c4 e6 3 Nc3 Bb4 4 Qc2 | 2 |
| E60 | King's Indian Defense | 1 d4 Nf6 2 c4 g6 | 2 |
| E62 | King's Indian, Fianchetto | 1 d4 Nf6 2 c4 g6 3 Nc3 Bg7 4 Nf3 d6 5 g3 | 2 |
| E68 | King's Indian, Fianchetto, Classical Variation, 8.e4 | 1 d4 Nf6 2 c4 g6 3 Nc3 Bg7 4 Nf3 d6 5 g3 O-O 6 Bg2 Nbd7 7 O-O e5 8 e4 | 2 |
| E70 | King's Indian | 1 d4 Nf6 2 c4 g6 3 Nc3 Bg7 4 e4 | 2 |
| A01 | Nimzovich-Larsen Attack | 1 b3 | 1 |
| A02 | Bird's Opening | 1 f4 | 1 |
| A09 | Reti Opening | 1 Nf3 d5 2 c4 | 1 |
| A11 | English, Caro-Kann Defensive System | 1 c4 c6 | 1 |
| A15 | English | 1 c4 Nf6 | 1 |
| A22 | English | 1 c4 e5 2 Nc3 Nf6 | 1 |
| A25 | English | 1 c4 e5 2 Nc3 Nc6 | 1 |
| A28 | English | 1 c4 e5 2 Nc3 Nc6 3 Nf3 Nf6 | 1 |
| A29 | English, Four Knights, Kingside Fianchetto | 1 c4 e5 2 Nc3 Nc6 3 Nf3 Nf6 4 g3 | 1 |
| A30 | English, Symmetrical | 1 c4 c5 | 1 |
| A32 | English, Symmetrical Variation | 1 c4 c5 2 Nf3 Nf6 3 d4 cxd4 4 Nxd4 e6 | 1 |
| A42 | Modern Defense, Averbakh System | 1 d4 d6 2 c4 g6 3 Nc3 Bg7 4 e4 | 1 |
| A43 | Old Benoni | 1 d4 c5 | 1 |
| A48 | King's Indian | 1 d4 Nf6 2 Nf3 g6 | 1 |
| A51 | Budapest Gambit | 1 d4 Nf6 2 c4 e5 | 1 |
| A52 | Budapest Gambit | 1 d4 Nf6 2 c4 e5 3 dxe5 Ng4 | 1 |
| A57 | Benko Gambit | 1 d4 Nf6 2 c4 c5 3 d5 b5 | 1 |
| A64 | Benoni, Fianchetto, 11...Re8 | 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 | 1 |
| A83 | Dutch, Staunton Gambit | 1 d4 f5 2 e4 fxe4 3 Nc3 Nf6 4 Bg5 | 1 |
| A84 | Dutch | 1 d4 f5 2 c4 | 1 |
| A90 | Dutch | 1 d4 f5 2 c4 Nf6 3 g3 e6 4 Bg2 | 1 |
| B03 | Alekhine's Defense | 1 e4 Nf6 2 e5 Nd5 3 d4 | 1 |
| B13 | Caro-Kann, Exchange | 1 e4 c6 2 d4 d5 3 exd5 cxd5 | 1 |
| B14 | Caro-Kann, Panov-Botvinnik Attack | 1 e4 c6 2 d4 d5 3 exd5 cxd5 4 c4 Nf6 5 Nc3 e6 | 1 |
| B15 | Caro-Kann | 1 e4 c6 2 d4 d5 3 Nc3 | 1 |
| B20 | Sicilian | 1 e4 c5 | 1 |
| B21 | Sicilian, 2.f4 and 2.d4 | 1 e4 c5 2 f4 | 1 |
| B24 | Sicilian, Closed | 1 e4 c5 2 Nc3 Nc6 3 g3 | 1 |
| B25 | Sicilian, Closed | 1 e4 c5 2 Nc3 Nc6 3 g3 g6 4 Bg2 Bg7 5 d3 d6 | 1 |
| B30 | Sicilian | 1 e4 c5 2 Nf3 Nc6 | 1 |
| B32 | Sicilian | 1 e4 c5 2 Nf3 Nc6 3 d4 cxd4 4 Nxd4 e5 | 1 |
| B50 | Sicilian | 1 e4 c5 2 Nf3 d6 | 1 |
| B62 | Sicilian, Richter-Rauzer | 1 e4 c5 2 Nf3 d6 3 d4 cxd4 4 Nxd4 Nf6 5 Nc3 Nc6 6 Bg5 e6 | 1 |
| B73 | Sicilian, Dragon, Classical | 1 e4 c5 2 Nf3 d6 3 d4 cxd4 4 Nxd4 Nf6 5 Nc3 g6 6 Be3 Bg7 7 Be2 Nc6 8 O-O | 1 |
| B78 | Sicilian, Dragon, Yugoslav Attack, 10.castle long | 1 e4 c5 2 Nf3 d6 3 d4 cxd4 4 Nxd4 Nf6 5 Nc3 g6 6 Be3 Bg7 7 f3 O-O 8 Qd2 Nc6 9 Bc4 Bd7 10 O-O-O | 1 |
| B84 | Sicilian, Scheveningen | 1 e4 c5 2 Nf3 d6 3 d4 cxd4 4 Nxd4 Nf6 5 Nc3 e6 6 Be2 a6 | 1 |
| B86 | Sicilian, Fischer-Sozin Attack | 1 e4 c5 2 Nf3 d6 3 d4 cxd4 4 Nxd4 Nf6 5 Nc3 e6 6 Bc4 | 1 |
| B94 | Sicilian, Najdorf | 1 e4 c5 2 Nf3 d6 3 d4 cxd4 4 Nxd4 Nf6 5 Nc3 a6 6 Bg5 | 1 |
| B96 | Sicilian, Najdorf | 1 e4 c5 2 Nf3 d6 3 d4 cxd4 4 Nxd4 Nf6 5 Nc3 a6 6 Bg5 e6 7 f4 | 1 |
| C02 | French, Advance | 1 e4 e6 2 d4 d5 3 e5 | 1 |
| C17 | French, Winawer, Advance | 1 e4 e6 2 d4 d5 3 Nc3 Bb4 4 e5 c5 | 1 |
| C24 | Bishop's Opening | 1 e4 e5 2 Bc4 Nf6 | 1 |
| C31 | King's Gambit Declined, Falkbeer Counter Gambit | 1 e4 e5 2 f4 d5 | 1 |
| C32 | King's Gambit Declined, Falkbeer Counter Gambit | 1 e4 e5 2 f4 d5 3 exd5 e4 4 d3 Nf6 | 1 |
| C35 | King's Gambit Accepted, Cunningham | 1 e4 e5 2 f4 exf4 3 Nf3 Be7 | 1 |
| C42 | Petrov Defense | 1 e4 e5 2 Nf3 Nf6 | 1 |
| C45 | Scotch Game | 1 e4 e5 2 Nf3 Nc6 3 d4 exd4 4 Nxd4 | 1 |
| C48 | Four Knights | 1 e4 e5 2 Nf3 Nc6 3 Nc3 Nf6 4 Bb5 | 1 |
| C49 | Four Knights | 1 e4 e5 2 Nf3 Nc6 3 Nc3 Nf6 4 Bb5 Bb4 | 1 |
| C52 | Evans Gambit | 1 e4 e5 2 Nf3 Nc6 3 Bc4 Bc5 4 b4 Bxb4 5 c3 Ba5 | 1 |
| C53 | Giuoco Piano | 1 e4 e5 2 Nf3 Nc6 3 Bc4 Bc5 4 c3 | 1 |
| C56 | Two Knights | 1 e4 e5 2 Nf3 Nc6 3 Bc4 Nf6 4 d4 exd4 5 O-O Nxe4 | 1 |
| C60 | Ruy Lopez | 1 e4 e5 2 Nf3 Nc6 3 Bb5 | 1 |
| C71 | Ruy Lopez | 1 e4 e5 2 Nf3 Nc6 3 Bb5 a6 4 Ba4 d6 | 1 |
| C92 | Ruy Lopez, Closed | 1 e4 e5 2 Nf3 Nc6 3 Bb5 a6 4 Ba4 Nf6 5 O-O Be7 6 Re1 b5 7 Bb3 O-O 8 c3 d6 9 h3 | 1 |
| D01 | Richter-Veresov Attack | 1 d4 d5 2 Nc3 Nf6 3 Bg5 | 1 |
| D05 | Queen's Pawn Game | 1 d4 d5 2 Nf3 Nf6 3 e3 e6 | 1 |
| D19 | Queen's Gambit Declined Slav, Dutch | 1 d4 d5 2 c4 c6 3 Nf3 Nf6 4 Nc3 dxc4 5 a4 Bf5 6 e3 e6 7 Bxc4 Bb4 8 O-O O-O 9 Qe2 | 1 |
| D23 | Queen's Gambit Accepted | 1 d4 d5 2 c4 dxc4 3 Nf3 Nf6 | 1 |
| D31 | Queen's Gambit Declined | 1 d4 d5 2 c4 e6 3 Nc3 | 1 |
| D32 | Queen's Gambit Declined, Tarrasch | 1 d4 d5 2 c4 e6 3 Nc3 c5 | 1 |
| D40 | Queen's Gambit Declined, Semi-Tarrasch | 1 d4 d5 2 c4 e6 3 Nc3 Nf6 4 Nf3 c5 | 1 |
| D43 | Queen's Gambit Declined Semi-Slav | 1 d4 d5 2 c4 e6 3 Nc3 Nf6 4 Nf3 c6 | 1 |
| D46 | Queen's Gambit Declined Semi-Slav | 1 d4 d5 2 c4 e6 3 Nc3 Nf6 4 Nf3 c6 5 e3 Nbd7 6 Bd3 | 1 |
| D53 | Queen's Gambit Declined | 1 d4 d5 2 c4 e6 3 Nc3 Nf6 4 Bg5 Be7 | 1 |
| D71 | Neo-Grunfeld | 1 d4 Nf6 2 c4 g6 3 g3 d5 | 1 |
| D90 | Grunfeld | 1 d4 Nf6 2 c4 g6 3 Nc3 d5 4 Nf3 | 1 |
| D93 | Grunfeld, with Bf4 & e3 | 1 d4 Nf6 2 c4 g6 3 Nc3 d5 4 Nf3 Bg7 5 Bf4 O-O 6 e3 | 1 |
| E06 | Catalan, Closed, 5.Nf3 | 1 d4 Nf6 2 c4 e6 3 g3 d5 4 Bg2 Be7 5 Nf3 | 1 |
| E14 | Queen's Indian | 1 d4 Nf6 2 c4 e6 3 Nf3 b6 4 e3 | 1 |
| E16 | Queen's Indian | 1 d4 Nf6 2 c4 e6 3 Nf3 b6 4 g3 Bb7 5 Bg2 Bb4+ | 1 |
| E20 | Nimzo-Indian | 1 d4 Nf6 2 c4 e6 3 Nc3 Bb4 | 1 |
| E43 | Nimzo-Indian, Fischer Variation | 1 d4 Nf6 2 c4 e6 3 Nc3 Bb4 4 e3 b6 | 1 |
| E61 | King's Indian | 1 d4 Nf6 2 c4 g6 3 Nc3 | 1 |
| E90 | King's Indian | 1 d4 Nf6 2 c4 g6 3 Nc3 Bg7 4 e4 d6 5 Nf3 | 1 |
| E91 | King's Indian | 1 d4 Nf6 2 c4 g6 3 Nc3 Bg7 4 e4 d6 5 Nf3 O-O 6 Be2 | 1 |
| E92 | King's Indian | 1 d4 Nf6 2 c4 g6 3 Nc3 Bg7 4 e4 d6 5 Nf3 O-O 6 Be2 e5 | 1 |