White 176 vs Black 583
White starts from setup 176 (BBNRNKRQ), Black from setup 583 (QRBNKRNB). In the encyclopedia since 2026-10-03: neither side starts better.
|cp| ≤ 5 at 400M · 800M · 1.6B · 4B nodes, two independent engines agree
The two setups
White: setup #176 B B N R N K R Q
King on the f-file, rooks on d, g, queen on the h-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 176 gives White +0.53 (Morozov Balance Index, 400M nodes).
Black: setup #583 Q R B N K R N B
King on the e-file, rooks on b, f, queen on the a-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 583 gives White +0.30 (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 59.
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 shallow rungs agreed early: from 100 thousand to 128 million nodes the evaluation never left ±15 cp.
For comparison, in symmetric play setup 176 gives White +0.53 and setup 583 gives White +0.30: 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 b3; the alternatives are slightly weaker but keep the game level.
Along the engine's main line (29 moves) the largest swing was 50 cp (around move 6), ending at 0 cp — the position stays playable for both sides.
Engine self-play agrees: 10 games, White won 0, drawn 9, Black won 1 (White scored 45.0%).
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 | +15 | 1. g4 g6 2. d4 b6 3. Qxa8 Rxa8 4. b3 |
| S1 | 500 000 | 19 | -2 | 1. g4 g6 2. d4 b5 3. Qxa8 Rxa8 4. b3 b4 |
| S2 | 2 000 000 | 22 | -8 | 1. g4 g6 2. d4 b5 3. Qxa8 Rxa8 4. b3 d6 |
| S3 | 8 000 000 | 28 | -13 | 1. g4 g6 2. c4 d6 3. d4 Nf6 4. h3 b5 |
| S4 | 32 000 000 | 35 | -8 | 1. g4 g6 2. c4 d6 3. d4 Nf6 4. h3 b5 |
| S5 | 128 000 000 | 43 | 0 | 1. b3 b5 2. h4 d6 3. Nf3 f5 4. e3 e5 |
| S6 | 400 000 000 | 51 | 0 | 1. b3 b5 2. h4 d6 3. Nf3 f5 4. e3 e5 |
| S7 | 800 000 000 | 55 | 0 | 1. b3 b5 2. e3 f5 3. Ne2 d6 4. d4 g6 |
| S8 | 1 600 000 000 | 59 | 0 | 1. b3 b5 2. e3 f5 3. h4 d6 4. Nf3 e5 |
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 | not checked |
| 8 000 000 000 | not checked |
| 16 000 000 000 | not checked |
This pair held exactly 0.00 up to 1 600 000 000 nodes.
Independent engines, run on the same position:
- Berserk 14: 0
- Lc0 0.32.1: -16
Independent confirmations: 2 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 +85, Black +70, difference +15. 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, 9 draws, 1 Black wins, White scored 45.0%.
Best first moves
The 3 best first moves for White, searched together at 400 000 000 nodes.
| # | Eval, cp | Depth | Main line |
|---|---|---|---|
| 1 | 0 | 39 | 1. b3 b5 2. e3 f5 3. Ne2 d6 4. d4 g6 5. O-O a5 |
| 2 | -21 | 39 | 1. g4 g6 2. d4 a5 3. b3 a4 4. b4 b5 5. Qxa8 Rxa8 |
| 3 | -38 | 38 | 1. h4 g6 2. g4 d6 3. c3 b5 4. Be4 Bb7 5. Bxb7 Qxb7 |
Main-line play-out
29 moves, 5 000 000 nodes per half-move. Largest |evaluation| 50 cp, mean 18.6 cp, final 0 cp.
| # | White | cp | Black | cp |
|---|---|---|---|---|
| 1 | g4 | -10 | g6 | -17 |
| 2 | c4 | -8 | a5 | -34 |
| 3 | h4 | -42 | Qa7 | -49 |
| 4 | g5 | -31 | e5 | -28 |
| 5 | b3 | -44 | d6 | -49 |
| 6 | h5 | -49 | Ne7 | -50 |
| 7 | Be4 | -42 | Ne6 | -48 |
| 8 | Ncd3 | -32 | Bd7 | -43 |
| 9 | hxg6 | -41 | hxg6 | -40 |
| 10 | f4 | -32 | O-O-O | -36 |
| 11 | fxe5 | -31 | Nc6 | -43 |
| 12 | Nf3 | -38 | dxe5 | -46 |
| 13 | Ndxe5 | -33 | Nxe5 | -22 |
| 14 | Nxe5 | -24 | Bxe5 | -23 |
| 15 | Bxe5 | -18 | Nxg5 | -14 |
| 16 | Rxg5 | -15 | f6 | -19 |
| 17 | Bxf6 | -16 | Rxf6+ | -10 |
| 18 | Bf3 | -8 | a4 | -6 |
| 19 | d4 | -4 | Bf5 | -3 |
| 20 | Qh4 | 0 | Re8 | 0 |
| 21 | Kg1 | 0 | Kb8 | 0 |
| 22 | e4 | 0 | Bc8 | 0 |
| 23 | Bg2 | 0 | Ref8 | 0 |
| 24 | Qe1 | 0 | Qa6 | 0 |
| 25 | Rg3 | 0 | Rf4 | 0 |
| 26 | e5 | 0 | Bg4 | 0 |
| 27 | Rdd3 | 0 | Bf5 | 0 |
| 28 | Rd1 | 0 | Bg4 | 0 |
| 29 | Rdd3 | 0 | Bf5 | 0 |
| 30 | Rd1 | 0 |
Engine self-play
10 games at 500 000 nodes per move: White won 0, drawn 9, Black won 1 — White scored 45.0%. Average length 43.2 moves.
Sample game 1 (0-1)
1. b3 b5 2. g3 Bb7 3. f3 d6 4. e4 e5 5. d4 f5 6. exf5 Ne7 7. g4 g6 8. dxe5 dxe5 9. Qg2 gxf5 10. Ncd3 Nf7 11. c4 O-O-O 12. gxf5 bxc4 13. bxc4 a5 14. Bc2 Ba6 15. f6 Bxf6 16. Nc5 Bxc4+ 17. Ned3 Nd5 18. Qg4+ Kb8 19. Kf2 Nb6 20. Bb3 Bxb3 21. axb3 Qc6 22. Qe4 Nd5 23. Qc4 Qb6 24. b4 axb4 25. Rb1 Be7 26. Rg7 Ng5 27. Rxg5 Rf4 28. Nxf4 Bxc5+ 29. Ke2 Nxf4+ 30. Kf1 Rd2 31. Bxe5 Rf2+ 32. Ke1 Ng2+ 33. Rxg2 Rxg2 34. Rb2 Qc6 35. Bxc7+ Kb7 36. Rxg2 Bf2+ 37. Rxf2 Qxc4 38. Be5 Kc6 39. f4 Qe4+ 40. Re2 Qh1+ 41. Kd2 Qf3 42. Ke1 h5 43. Rf2 Qh1+ 44. Kd2 Qe4 45. Bb2 Kd5 46. f5 Kc4 47. Bh8 Qd3+ 48. Ke1 Qe3+ 49. Kf1 h4 50. Rg2 Qd3+ 51. Ke1 Qb1+ 52. Kf2 Qxf5+ 53. Ke1 h3 54. Rg3 Qe4+ 55. Kd1 Qf4 56. Rg7 Qxh2 57. Rg4+ Kb3 58. Bb2 Qc2+ 59. Ke1 h2 60. Rh4
Sample game 2 (1/2-1/2)
1. g4 g6 2. c4 c5 3. h4 b5 4. Qxa8 Rxa8 5. cxb5 Rb8 6. Bd3 d5 7. Bc2 Nf6 8. a4 Bxg4 9. f3 Bh3+ 10. Kf2 Nd7 11. e3 a6 12. bxa6 Nc6 13. Ne2 Bf6 14. Nf4 Bxh4+ 15. Ke2 Nb4 16. a7 Ra8 17. Bb1 Bxe1 18. Rdxe1 Rxa7 19. b3 Bf5 20. Bxf5 gxf5 21. Bc3 Rb7 22. Rb1 e5 23. Bxb4 exf4 24. Bc3 fxe3 25. dxe3 Ke7 26. b4 Ra8 27. a5 cxb4 28. Rxb4 Rxb4 29. Bxb4+ Ke6 30. Rc1 Ne5 31. Rc7 Nc4 32. Rc6+ Kd7 33. Rf6 Nxa5 34. Rxf7+ Ke6 35. Rxh7 Nc4 36. f4 Kf6 37. Kd3 Nb2+ 38. Kd2 Nc4+ 39. Kd3 Kg6 40. Rd7 Rb8
Play it in the CH960 app
Open this page on a phone with the CH960 app installed, or find pair 176 / 583 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): qrbnkrnb/pppppppp/8/8/8/8/PPPPPPPP/BBNRNKRQ w DGbf - 0 1
Mirror twin (the same position mirrored): White 783 vs Black 274.
Current place in the live balance rating: 142.