ChessPuzzlePrint
Berlin Defense
Play through the 31 named Berlin Defense lines and see the name and ECO code of each position.
What this berlin defense page does
The Berlin Defense explorer is a free, browser-based tool for the Berlin Defense, Black's reply 3...Nf6 in the Ruy Lopez. It lists the named lines of this opening from a catalogue of about 3,800 named opening lines, and it plays any line you pick on a board so you can step through it move by move. Everything runs in your web browser. There is no sign-up, and nothing is uploaded. Every move on the board is checked by the chess.js library, which applies the chess rules. The page shows named lines and positions only. It has no engine evaluation, win percentages, master games or statistics.
How to use the Berlin Defense opening explorer
- The page opens on the main line named in the heading, with all its moves already played.
- Use ⏮ to go back to the start, ◀ to go back one move, ▶ to go forward one move and ⏭ to jump to the last move.
- Press Auto-play to play one move about every 1.1 seconds. The button turns into Pause, so press it again to stop.
- Press Flip board to view the position from Black's side.
- Read the line under the buttons. It shows the moves played so far and, when the catalogue knows the position, its name and ECO code.
- In the Lines list on the right, click any row to play that line. Each row shows the ECO code, the name and the moves.
- Under Moves of the selected line, click any move to jump straight to that position.
- Press 'Practise this line in the opening trainer' to open the opening trainer on the same line.
- Click any move under Moves of the selected line to jump straight to that position, or press ⏮ to go back to the start.
- Press Flip board to look at the position from Black's side, and use Auto-play to watch the line run by itself.
The address bar keeps the line you chose (the ?l= part of the address), so copying the address and sending it to someone opens the same line.
What is the Berlin Defense?
The Berlin Defense is Black's reply 3...Nf6 in the Ruy Lopez, which begins 1.e4 e5 2.Nf3 Nc6 3.Bb5. The catalogue calls it 'Ruy Lopez: Berlin Defense' and gives it the ECO code C65. The name is also written as Berlin defence, and both spellings refer to the same opening.
ECO stands for Encyclopaedia of Chess Openings. Its codes run from A00 to E99, and each letter covers a family of openings. The letter C covers open games and the French, so the Berlin Defense sits among the open games. The catalogue holds 31 named lines in the Berlin Defense family, coded C65, C66 and C67. The longest has 26 half-moves and is the Rio de Janeiro Variation.
What are the moves of the Berlin Defense?
After 3...Nf6, several named branches follow. One branch is 4.O-O Nxe4, which the catalogue names the Rio Gambit Accepted. Other branches begin with 4.O-O Bc5 (Beverwijk Variation), 4.O-O Ng4 (Fishing Pole Variation) and 4.d4 exd4 5.O-O (Nyholm Attack).
The closed lines (Bernstein, Showalter, Wolf and Hedgehog) arrive after 4.O-O d6 5.d4 Bd7 6.Nc3. The Improved Steinitz Defense is 4.O-O d6, a separate branch.
The catalogue names a position by its pieces, not by the order of the moves. Two different move orders that reach the same position therefore show the same name, so a name in the tool tells you about the position on the board, not only the sequence you played.
Examples
Questions and answers
What is the Berlin Wall in chess?
The Berlin Wall is the line 4.O-O Nxe4 5.d4 Nd6 6.Bxc6 dxc6 7.dxe5 Nf5 8.Qxd8+ Kxd8 9.Nc3 Bd7 (ECO C67). The queens are traded early, and Black's king has recaptured on d8. The catalogue calls it the l'Hermet Variation, Berlin Wall Defense.
What is the Anti-Berlin?
The Anti-Berlin is White's 4.d3 instead of castling, which is coded C65. The named lines are the Anderssen Variation (4...d6 5.Bxc6+), the Duras Variation (4...d6 5.c4), the Kaufmann Variation (4...Bc5 5.Be3) and the Mortimer Variation (4...Ne7 with the Mortimer Trap, 5.Nxe5 c6).
How do I practise the Berlin Defense?
Open a line in the Lines list or the Moves of the selected line, then press 'Practise this line in the opening trainer'. The trainer opens on the same line, so you can practise the moves from that point.
Does the tool show engine evaluations or win rates?
No. The tool shows named lines and positions only. It does not show engine evaluations, win percentages, master games or statistics.
Does the Berlin Defense explorer cost anything or need an account?
No. The tool is free, needs no sign-up, and nothing you do is uploaded, because everything runs in your browser.
Why does one position show the same name after different move orders?
The catalogue names a position by its pieces rather than by the order of moves. Two move orders that reach the same position therefore show the same name and ECO code.
Related chess tools
Open-source components used by this tool: chess.js (BSD-2-Clause); chess-openings catalogue (CC0-1.0).