Openings
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Codex of Opening Systems
All 126 opening families in one catalogue: search by name, move or player, and filter by the kind of position.
Key set-ups
51 families
ECO D06Article2.c4Tabiya: 7…b6257 linesQueen's Gambit
- Closed games
- Positional play
Offer a pawn, build a fortress
Study opening- ECO E616…e5Tabiya: 8…Ne7119 lines
King's Indian Defense
- Semi-closed games
- Fianchetto
- Sharp play
- Closed centre
Let White build the centre: it will become a target
Study opening - ECO E203…Bb4Tabiya: 7…Nc699 lines
Nimzo-Indian Defense
- Semi-closed games
- Positional play
- Hypermodern
A pin instead of a centre
Study opening - ECO D80Article3…d5Tabiya: 6…Bg759 lines
Grünfeld Defense
- Semi-closed games
- Sharp play
- Big pawn centre
- Hypermodern
Give up the centre, then take it apart
Study opening - ECO D102…c6Tabiya: 8…Nbd752 lines
Slav Defense
- Closed games
- Solid
A pawn on c6, a bishop at large
Study opening - ECO D434…e6Tabiya: 9…c570 lines
Semi-Slav Defense
- Closed games
- Sharp play
The bishop is shut in, but not for long
Study opening - ECO E123…b6Tabiya: 7…Ne473 lines
Queen's Indian Defense
- Semi-closed games
- Fianchetto
- Positional play
- Hypermodern
A bishop on b7 stares across the whole board
Study opening - ECO A801…f5Tabiya: 6…d669 lines
Dutch Defense
- Semi-closed games
- Fianchetto
- Sharp play
- Closed centre
One pawn step, and e4 is in the fist
Study opening - ECO E003.g3Tabiya: 8…b532 lines
Catalan Opening
- Closed games
- Fianchetto
- Positional play
The queen's gambit with a bishop on g2
Study opening - ECO A565.cxd5Tabiya: 7…Bg761 lines
Benoni Defense
- Semi-closed games
- Sharp play
- Asymmetry
White gets the centre, Black gets the wing and the diagonal
Study opening - ECO A483.Bf4Tabiya: 6…Nbd78 lines
London System
- Closed games
- Solid
- Set-up systems
One setup against almost anything
Study opening - ECO A573…b5Tabiya: 8…g624 lines
Benko Gambit
- Semi-closed games
- Gambits
- Sharp play
- Asymmetry
A pawn for open files
Study opening - ECO A401…Na6Tabiya: 3…d51 lines
Australian Defense
- Semi-closed games
- Offbeat
A knight on the rim at move one
Study opening - ECO A401…b6Tabiya: 6…Nf67 lines
English Defense
- Semi-closed games
- Fianchetto
- Hypermodern
Let them build the centre; we will undermine it
Study opening - ECO A401…e5Tabiya: 6.Nc316 lines
Englund Gambit
- Semi-closed games
- Gambits
- Sharp play
A pawn on credit, the queen on a raid
Study opening - ECO A401…e6Tabiya: 4…Be72 lines
Horwitz Defense
- Semi-closed games
- Offbeat
A waiting move: French, Queen's Gambit or Dutch, to be decided later
Study opening - ECO A402…Bb4+Tabiya: 4…d52 lines
Kangaroo Defense
- Semi-closed games
- Offbeat
Check on move two and a flexible plan
Study opening - ECO A401…Nc6Tabiya: 5.Nf34 lines
Mikenas Defense
- Semi-closed games
- Offbeat
The knight steps out before White has shown a plan
Study opening - ECO A402…Nb8Tabiya: 4…e61 lines
Montevideo Defense
- Semi-closed games
- Offbeat
The knight goes out and comes straight back
Study opening - ECO A401…b5Tabiya: 2…Bb72 lines
Polish Defense
- Semi-closed games
- Offbeat
The flank pawn goes first, the centre can wait
Study opening - ECO A401.d4Tabiya: 7…Nc682 lines
Queen's Pawn Game
- Closed games
One move, many roads
Study opening - ECO A404…Ng8Tabiya: 4…Ng81 lines
Zaire Defense
- Semi-closed games
- Offbeat
Two knights stepped out and came straight back
Study opening - ECO A415…Be7Tabiya: 7…c614 lines
Old Indian Defense
- Semi-closed games
- Solid
An Indian defence where the bishop stays at home
Study opening - ECO A4111 lines
Rat Defense
- Semi-open games
- Offbeat
Study opening - ECO A411 lines
Robatsch Defense
- Semi-closed games
- Fianchetto
- Hypermodern
Study opening - ECO A412…Bg4Tabiya: 4…e51 lines
Wade Defense
- Semi-closed games
- Offbeat
The bishop comes out first; the pawns can wait
Study opening - ECO A452.b3Tabiya: 4…c51 lines
Basque Opening
- Semi-closed games
- Offbeat
A bishop on b2 with its own d4 pawn in the way
Study opening - ECO A452.f4Tabiya: 4…c51 lines
Canard Opening
- Semi-closed games
- Offbeat
The f4 pawn against the f6 knight: a Dutch-style set-up with White
Study opening - ECO A451…Nf6Tabiya: 5…O-O53 lines
Indian Defense
- Semi-closed games
- Hypermodern
Let them build a centre; we shall deal with it later
Study opening - ECO A452.f3Tabiya: 5.Nxf31 lines
Paleface Attack
- Semi-closed games
- Offbeat
A pawn that takes a square from its own knight
Study opening - ECO A452.Bg5Tabiya: 4…c510 lines
Trompowsky Attack
- Semi-closed games
- Set-up systems
The bishop is out before you have opened your theory book
Study opening - ECO A462…Ne4Tabiya: 4…d51 lines
Döry Defense
- Semi-closed games
- Offbeat
A knight jump to e4 on move two
Study opening - ECO A466 lines
Torre Attack
- Closed games
- Set-up systems
Study opening - ECO A463.e3Tabiya: 6.Ne51 lines
Yusupov-Rubinstein System
- Closed games
- Set-up systems
A quiet set-up: e3, Bd3 and a knight on e5
Study opening - ECO A474…c5Tabiya: 6.Nxd42 lines
Marienbad System
- Semi-closed games
- Fianchetto
- Set-up systems
A Queen's Indian set-up with …c5 thrown in early
Study opening - ECO A472…b6Tabiya: 3…e62 lines
Pseudo Queen's Indian Defense
- Semi-closed games
- Fianchetto
- Hypermodern
A Queen's Indian with the moves swapped
Study opening - ECO A482…g6Tabiya: 5…d61 lines
East Indian Defense
- Semi-closed games
- Fianchetto
- Hypermodern
The King's Indian, minus the c4 for now
Study opening - ECO A502…Nc6Tabiya: 4…Bb42 lines
Mexican Defense
- Semi-closed games
- Offbeat
A knight on c6 where a pawn usually goes
Study opening - ECO A502…b6Tabiya: 4…e61 lines
Queen's Indian Accelerated
- Semi-closed games
- Fianchetto
- Hypermodern
The bishop's diagonal first, the e6 pawn later
Study opening - ECO A502…c6Tabiya: 3…d52 lines
Slav Indian
- Semi-closed games
- Solid
Slav or Indian: Black has not decided yet
Study opening - ECO A563…Ne4Tabiya: 5…Nd61 lines
Vulture Defense
- Semi-closed games
- Offbeat
The knight bolts ahead while everyone else is still at home
Study opening - ECO D002.Qd3Tabiya: 3…c52 lines
Amazon Attack
- Closed games
- Offbeat
The queen out early, the bishop shut in
Study opening - ECO D004.f3Tabiya: 5…c649 lines
Blackmar-Diemer Gambit
- Closed games
- Gambits
- Sharp play
- Big pawn centre
A pawn for time and an open f-file
Study opening - ECO D013.Bf4Tabiya: 4…Na64 lines
Rapport-Jobava System
- Closed games
- Sharp play
- Set-up systems
A London with a knight eyeing c7
Study opening - ECO D013.Bg5Tabiya: 4.f38 lines
Richter-Veresov Attack
- Closed games
- Set-up systems
The bishop goes first, the c-pawn stays home
Study opening - ECO D055.b3Tabiya: 7…O-O6 lines
Rubinstein Opening
- Closed games
- Positional play
A Colle with the bishop rushing to b2
Study opening - ECO D323…c5Tabiya: 7…Be727 lines
Tarrasch Defense
- Closed games
- Sharp play
- Isolated pawn
A weak pawn for free pieces
Study opening - ECO D7016 lines
Neo-Grünfeld Defense
- Semi-closed games
- Fianchetto
- Hypermodern
Study opening - ECO E104…b5Tabiya: 6…d54 lines
Blumenfeld Countergambit
- Semi-closed games
- Gambits
- Sharp play
A wing pawn for the centre
Study opening - ECO E113…Bb4+Tabiya: 7…Ne421 lines
Bogo-Indian Defense
- Semi-closed games
- Solid
A bishop check that sidesteps the big theory
Study opening