White 267 vs Black 672
White starts from setup 267 (NRKNBQRB), Black from setup 672 (BBQRKNNR). In the encyclopedia since 2026-10-09: neither side starts better.
|cp| ≤ 5 at 400M · 800M · 1.6B · 4B nodes, two independent engines agree
The two setups
White: setup #267 N R K N B Q R B
King on the c-file, rooks on b, g, queen on the f-file; one bishop starts in a corner; the knights start away from the centre. The king already stands on a castled square, so one of the castlings moves only the rook. In ordinary symmetric play setup 267 gives White +0.23 (Morozov Balance Index, 400M nodes).
Black: setup #672 B B Q R K N N R
King on the e-file, rooks on d, h, queen on the c-file; one bishop starts in a corner; the knights start on central files. Castling follows the Chess960 rule: king and rook end on the classical squares. In ordinary symmetric play setup 672 gives White +0.26 (Morozov Balance Index, 400M nodes).
Why the pair is balanced
At the deepest rungs (400M, 800M, 1.6B nodes) the evaluation is exactly 0.00 each time, reaching search depth 61.
Admission rule: |cp| ≤ 5 at four budgets up to 4 billion nodes, no one-sided drift along the ladder, and confirmation by two independent engines — Berserk and Lc0 — each below its own median on symmetric positions. The same corridor is required at every deeper budget (8 G, 16 G) at which the pair has been evaluated.
The shallow rungs wandered between -30 and +7 cp before settling — a reminder that quick engine checks overstate imbalances, and why the ladder goes deep.
For comparison, in symmetric play setup 267 gives White +0.23 and setup 672 gives White +0.26: with both sides on the same rank the first move is worth something. In this pair Black's own setup absorbs that edge completely.
The engine's first choice for White is e4; the alternatives are slightly weaker but keep the game level.
Along the engine's main line (29 moves) the evaluation stayed within ±29 cp the whole way: the balance holds as the pieces come out, not only on move one.
Engine self-play agrees: 10 games, White won 0, drawn 5, Black won 5 (White scored 25.0%).
Verification ladder
Nine independent searches of the starting position, each with a larger node budget. Evaluation in centipawns from White's point of view.
| Stage | Nodes | Depth | Eval, cp | Main line |
|---|---|---|---|---|
| S0 | 100 000 | 12 | -30 | 1. g4 c5 2. f4 d5 3. b4 b6 4. bxc5 bxc5 |
| S1 | 500 000 | 18 | -2 | 1. e4 d5 2. exd5 Nf6 3. g3 Nxd5 4. b4 c6 |
| S2 | 2 000 000 | 25 | -1 | 1. e4 d5 2. exd5 Nf6 3. g3 Nxd5 4. d4 Ne6 |
| S3 | 8 000 000 | 32 | -2 | 1. e4 b6 2. g3 c5 3. f4 d5 4. exd5 Bxd5 |
| S4 | 32 000 000 | 34 | +7 | 1. e4 b6 2. g3 c5 3. c4 Ne6 4. Ne3 Nd4 |
| S5 | 128 000 000 | 44 | 0 | 1. e4 b6 2. g3 c5 3. f4 d5 4. exd5 Bxd5 |
| S6 | 400 000 000 | 53 | 0 | 1. e4 b6 2. g3 c5 3. c4 f5 4. exf5 Bxh1 |
| S7 | 800 000 000 | 54 | 0 | 1. e4 b6 2. g3 c5 3. f4 d5 4. exd5 Bxd5 |
| S8 | 1 600 000 000 | 61 | 0 | 1. e4 b6 2. g3 c5 3. c4 f5 4. exf5 Bxh1 |
Deep verification
The search ladder reaches 1.6 billion nodes; admission needs a 4-billion rung and two further engines on top of that. Beyond even that, every pair was re-checked at budgets up to ten times larger and in thousands of self-play games. This section shows what each check returned for this pair.
| Nodes | Eval, cp |
|---|---|
| 4 000 000 000 | 0 |
| 8 000 000 000 | not checked |
| 16 000 000 000 | not checked |
This pair stays within the ±5 cp corridor up to 4 000 000 000 nodes.
Independent engines, run on the same position:
- Berserk 14: 0
- Lc0 0.32.1: -4
Independent confirmations: 3 of 3. An engine counts as confirming when its reading of the pair is closer to equality than its own reading of a typical symmetric Chess960 position (+10 for Berserk, +18 for Lc0). Where only one engine confirms, the pair is balanced according to that engine alone, and this page says so.
Own weight of each setup, measured against the classical array: White +86, Black +156, difference -70. A balanced pair needs White's setup to be weaker by about the price of the first move.
Extended self-play: 10 games, 0 White wins, 5 draws, 5 Black wins, White scored 25.0%.
Best first moves
The 3 best first moves for White, searched together at 400 000 000 nodes.
| # | Eval, cp | Depth | Main line |
|---|---|---|---|
| 1 | -8 | 43 | 1. e4 b6 2. g3 c5 3. f4 d5 4. exd5 Bxd5 5. Bxd5 Rxd5 |
| 2 | -25 | 42 | 1. g4 d5 2. f4 b6 3. e3 c5 4. c4 Bb7 5. Bxd5 Bxd5 |
| 3 | -25 | 42 | 1. f4 d5 2. e3 c5 3. g4 b6 4. c4 e6 5. h4 Bc6 |
Main-line play-out
29 moves, 5 000 000 nodes per half-move. Largest |evaluation| 29 cp, mean 10.5 cp, final 0 cp.
| # | White | cp | Black | cp |
|---|---|---|---|---|
| 1 | e4 | -5 | b6 | -2 |
| 2 | g3 | -1 | c5 | -4 |
| 3 | c4 | -7 | Ne6 | -15 |
| 4 | Nc3 | -15 | Nd4 | -10 |
| 5 | f4 | -19 | f5 | -6 |
| 6 | d3 | -16 | e5 | -17 |
| 7 | O-O-O | -23 | Nf6 | -19 |
| 8 | Nc2 | -26 | O-O | -27 |
| 9 | Bd2 | -25 | Rde8 | -20 |
| 10 | Re1 | -19 | Bc6 | -23 |
| 11 | Kb1 | -29 | b5 | -21 |
| 12 | cxb5 | -15 | Nxb5 | -18 |
| 13 | exf5 | -26 | Nxc3+ | -11 |
| 14 | Bxc3 | -16 | Bxh1 | -23 |
| 15 | Rxh1 | -23 | exf4 | -19 |
| 16 | Rxe8 | -19 | Nxe8 | -16 |
| 17 | gxf4 | -10 | d5 | -14 |
| 18 | Be5 | -13 | Bxe5 | -8 |
| 19 | fxe5 | -14 | Rxf5 | -14 |
| 20 | Qh3 | -11 | d4 | -1 |
| 21 | Na1 | 0 | Qe6 | 0 |
| 22 | Re1 | 0 | Nc7 | 0 |
| 23 | Nb3 | 0 | Rxe5 | 0 |
| 24 | Qxe6+ | 0 | Rxe6 | 0 |
| 25 | Rc1 | 0 | Re5 | 0 |
| 26 | Nxc5 | 0 | Re2 | 0 |
| 27 | Rc2 | 0 | Re1+ | 0 |
| 28 | Rc1 | 0 | Re2 | 0 |
| 29 | Rc2 | 0 | Re1+ | 0 |
| 30 | Rc1 | 0 |
Engine self-play
10 games at 500 000 nodes per move: White won 0, drawn 5, Black won 5 — White scored 25.0%. Average length 58.5 moves.
Sample game 1 (0-1)
1. g3 d5 2. e4 dxe4 3. Bxe4 Nf6 4. Bg2 e5 5. Ne3 Ne6 6. f4 c5 7. O-O-O O-O 8. f5 Nd4 9. d3 h6 10. Nb3 e4 11. dxe4 b5 12. Nxd4 cxd4 13. Nd5 Bxd5 14. exd5 Nxd5 15. Bxd5 Rxd5 16. Qd3 Re8 17. Bc3 Bc7 18. Bxd4 Qd7 19. c3 Bb6 20. Qf3 Bxd4 21. Rxd4 Rxd4 22. cxd4 Qxd4 23. Rd1 Qc5+ 24. Kb1 b4 25. Rc1 Qd4 26. f6 g6 27. h4 h5 28. Rd1 Qc4 29. a3 bxa3 30. Qxa3 Qg4 31. Qd3 Re6 32. Rf1 Qa4 33. Qd8+ Re8 34. Qd3 Qc6 35. Qb3 Qe4+ 36. Qc2 Qd5 37. Rd1 Qf3 38. Rd3 Qxf6 39. Qc3 Qf5 40. Ka2 Rc8 41. Qd2 Qe6+ 42. Kb1 Rc5 43. Rd7 Rf5 44. Qd3 Qf6 45. Rd6 Qe5 46. Rd7 a6 47. Rd4 Qe1+ 48. Ka2 Qe6+ 49. Kb1 Kh7 50. Re4 Qb6 51. Qc3 Qb5 52. Re3 Qd5 53. Qd3 Qh1+ 54. Ka2 Ra5+ 55. Kb3 Qc1 56. Re2 Qa1 57. Qd4 Qa2+ 58. Kc2 Rd5 59. Qb4 Rb5 60. Qd4 Qb3+ 61. Kb1 Rf5 62. Rf2 Qxg3 63. Rxf5 gxf5 64. Ka2 Qg4 65. Qd6 f4 66. Ka3 Qxh4 67. b4 Qh3+ 68. Kb2 f3 69. Qf6 Qg4 70. Ka3 Kg8 71. Ka4 Qd7+ 72. Ka3 Qd3+ 73. Kb2 Qe3 74. Qd8+ Kg7 75. Qd5 f2 76. Qxh5 Qf4 77. Qc5 f1=Q 78. Qc3+ Qf6 79. Kb3
Sample game 2 (1/2-1/2)
1. e4 b6 2. g3 c5 3. Nc3 e6 4. O-O-O d5 5. exd5 exd5 6. d4 c4 7. Bd2 Ne6 8. Re1 Ne7 9. f4 Nxd4 10. Qf2 Nc6 11. Nxd5 Bd6 12. f5 O-O 13. f6 Nxd5 14. fxg7 Rfe8 15. Bxd5 Qd7 16. Rxe8+ Rxe8 17. Rd1 Bc5 18. Qg2 Rd8 19. Bf3 Ne5 20. Bxa8 c3 21. Qe2 Nc4 22. Qxc4 cxd2+ 23. Kb1 Rxa8 24. Qd3 Qxd3 25. cxd3 Be3 26. Nc2 Bh6 27. Nd4 Rc8 28. Nb3 Rd8 29. Kc2 Rc8+ 30. Kb1 Rd8 31. Kc2 Rc8+
Play it in the CH960 app
Open this page on a phone with the CH960 app installed, or find pair 267 / 672 in the app's encyclopedia, then choose how to play.
- Local game — two players on one device, with a clock.
- With a mentor — a clearly labelled training bot with hints, at your level.
- Challenge a friend — an online game by link; both players get the same pair, colours swap on rematch.
Play this pair against the computer, right here Play a friend
FEN (Shredder, castling rights by rook files): bbqrknnr/pppppppp/8/8/8/8/PPPPPPPP/NRKNBQRB w BGdh - 0 1
Mirror twin: White 593 vs Black 479 — a different position (castling squares are fixed), not evaluated by the search.