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.

1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. a3 ◀ Undo move

♞ You have reached Nimzo-Indian Defense: Sämisch Variation E24 — the catalogued line ends exactly here.

Book continuations

Bxc3+ 3

Matching openings 4

Nimzo-Indian Defense: Sämisch Variation E27 3 plies deeper
Nimzo-Indian Defense: Sämisch Variation E26 4 plies deeper
Nimzo-Indian Defense: Sämisch Variation, O'Kelly Variation E26 5 plies deeper

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

3810 catalogued lines in total · openings encyclopedia