Opening explorer

Walk any move order through the catalog: pick a book continuation and watch the board, or open the matching ECO lines on the side. Move orders, not transpositions — exactly the paths over the board. Prefer the family trees? Every opening page has one.

a8b7c6d5e4f3g2h1
1. e4 e6 2. d4 d5 3. Nc3 Nf6 4. Bg5 dxe4 5. Nxe4 Be7 ◀ Undo move

♞ You have reached French Defense: Classical Variation C13 — the catalogued line ends exactly here.

Book continuations

Matching openings 3

…and 1 more lines run through this position — keep making moves to narrow it down.

3810 catalogued lines in total · openings encyclopedia