The Library

Chess openings

Every Encyclopedia of Chess Openings classification — 3,161 lines from A00 to E99, with interactive playback and family hierarchy. Statistics from 2,808 positions tracked in master play.

Most played

Frequency in master games, from Lichess Masters DB.

  1. 1 King's Pawn Game B00 1,309,466 games
  2. 2 Queen's Pawn Game A40 1,029,878 games
  3. 3 Indian Defense A45 626,798 games
  4. 4 Sicilian Defense B20 601,092 games
  5. 5 Indian Defense: Normal Variation A50 456,632 games
  6. 6 Zukertort Opening A04 292,958 games
  7. 7 King's Knight Opening C40 289,898 games
  8. 8 King's Knight Opening: Normal Variation C44 249,218 games
  9. 9 Sicilian Defense: Modern Variations B50 231,200 games
  10. 10 Queen's Gambit D06 204,463 games
  11. 11 English Opening A10 199,442 games
  12. 12 Sicilian Defense: Modern Variations, Main Line B54 171,576 games

Highest White scoring

Win % for White, ≥ 1,500 master games.

  1. 53.4% Benoni Defense: Semi-Benoni A44 · 1,594 games
  2. 48.3% Benoni Defense: Taimanov Variation A67 · 1,950 games
  3. 46.6% Benoni Defense: Pawn Storm Variation A66 · 2,323 games
  4. 45.5% Owen Defense B00 · 1,940 games
  5. 45.3% Benoni Defense: Knight's Tour Variation A61 · 2,223 games
  6. 45.3% Sicilian Defense: Accelerated Dragon, Maróczy Bind, Breyer Variation B39 · 1,993 games

Highest Black scoring

Win % for Black, ≥ 1,500 master games.

  1. 36.8% Rat Defense: English Rat A41 · 4,324 games
  2. 36.6% Sicilian Defense: Godiva Variation B32 · 3,777 games
  3. 36.4% Sicilian Defense: Grand Prix Attack B23 · 4,305 games
  4. 36.2% King's Gambit Accepted C33 · 3,315 games
  5. 36.1% Richter-Veresov Attack D01 · 4,018 games
  6. 36.0% Sicilian Defense: Sozin Attack, Flank Variation B87 · 2,689 games

Browse by ECO volume

A

Volume A

Flank openings and irregular

672 lines
B

Volume B

Semi-open games, Sicilian

674 lines
C

Volume C

1.e4 e5 and the French

1089 lines
D

Volume D

Closed games, Queen's Gambit

458 lines
E

Volume E

Indian defences

268 lines

The Encyclopedia of Chess Openings divides theory into five volumes (A–E), each containing one hundred two-digit codes (00–99). Every code identifies a specific position reached by a defined move order. We carry every code; each page includes an interactive playable board, the canonical PGN, parent/sibling/child variations, and — for the most-studied lines — full editorial articles.