White 56 vs Black 819
White starts from setup 56 (NBNRBQKR), Black from setup 819 (BRKNQRNB). In the encyclopedia since 2026-11-01: neither side starts better.
|cp| ≤ 5 at 400M · 800M · 1.6B · 4B nodes, two independent engines agree
How to play with different setups
White sets up the pieces by position No. 56, Black by position No. 819, mirrored on their own side; the pawns stand as usual.
Moves as usual: White starts; everything else follows the Chess960 rules.
The two setups
White: setup #56 N B N R B Q K R
King on the g-file, rooks on d, h, queen on the f-file; no 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 56 gives White +0.44 (Morozov Balance Index, 400M nodes).
Black: setup #819 B R K N Q R N B
King on the c-file, rooks on b, f, queen on the e-file; one bishop starts in a corner; the knights start on central files. The king already stands on a castled square, so one of the castlings moves only the rook. In ordinary symmetric play setup 819 gives White +0.16 (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 54.
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 -20 and +5 cp before settling — a reminder that quick engine checks overstate imbalances, and why the ladder goes deep.
For comparison, in symmetric play setup 56 gives White +0.44 and setup 819 gives White +0.16: with both sides on the same rank the first move is worth something. In this pair Black's own setup absorbs that edge completely.
White is not forced into a single path: the best first move is d4, and 3 first moves are within 10 cp of it.
Along the engine's main line (30 moves) the largest swing was 38 cp (around move 8), ending at +17 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 | 14 | -17 | 1. c3 f5 2. e3 b6 3. f3 e5 4. Qb5 Bc6 |
| S1 | 500 000 | 20 | +5 | 1. c4 g6 2. d4 f5 3. e3 e5 4. Nab3 b6 |
| S2 | 2 000 000 | 22 | -9 | 1. d4 e5 2. e3 f5 3. dxe5 Qxe5 4. c4 b6 |
| S3 | 8 000 000 | 26 | -6 | 1. c4 e5 2. e3 g6 3. d4 f5 4. Bb4 d6 |
| S4 | 32 000 000 | 32 | -20 | 1. c4 f5 2. d4 g6 3. e3 e5 4. Nc2 b6 |
| S5 | 128 000 000 | 40 | -14 | 1. d4 f5 2. c4 g6 3. Nc2 Nf7 4. e3 e5 |
| S6 | 400 000 000 | 45 | 0 | 1. d4 f5 2. c4 g6 3. e3 e5 4. Nc2 Nf7 |
| S7 | 800 000 000 | 48 | 0 | 1. d4 f5 2. c4 g6 3. e3 e5 4. Nc2 Nf7 |
| S8 | 1 600 000 000 | 54 | 0 | 1. d4 f5 2. c4 g6 3. e3 e5 4. Nc2 Nf7 |
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: +4
- 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 +104, Black +103, difference +1. 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 | +7 | 41 | 1. d4 e5 2. e3 exd4 3. exd4 Nf6 4. c3 Ne6 5. Bd2 b6 |
| 2 | -2 | 41 | 1. e3 g6 |
| 3 | -2 | 41 | 1. c4 f5 2. d4 g6 3. e3 e5 4. Nc2 Nf7 5. Qe2 b6 |
Main-line play-out
30 moves, 5 000 000 nodes per half-move. Largest |evaluation| 38 cp, mean 21.8 cp, final +17 cp.
| # | White | cp | Black | cp |
|---|---|---|---|---|
| 1 | c4 | -13 | e5 | -20 |
| 2 | e3 | -3 | g6 | 0 |
| 3 | d4 | +6 | b6 | -6 |
| 4 | Ne2 | +7 | f5 | +13 |
| 5 | Bb4 | +6 | d6 | +12 |
| 6 | d5 | +27 | e4 | +29 |
| 7 | Bc3 | +31 | Be5 | +27 |
| 8 | Nb3 | +38 | b5 | +32 |
| 9 | Bxe5 | +34 | Qxe5 | +37 |
| 10 | Nc3 | +36 | bxc4 | +34 |
| 11 | Qxc4 | +19 | Nf6 | +26 |
| 12 | Bc2 | +22 | Nf7 | +33 |
| 13 | h3 | +31 | O-O | +24 |
| 14 | O-O | +35 | g5 | +25 |
| 15 | Qd4 | +26 | Qxd4 | +23 |
| 16 | Rxd4 | +21 | Ne5 | +22 |
| 17 | Rfd1 | +18 | a6 | +14 |
| 18 | Ra4 | +26 | Rb6 | +21 |
| 19 | Rd2 | +20 | Kh8 | +25 |
| 20 | Bd1 | +24 | h5 | +19 |
| 21 | Be2 | +31 | Bb7 | +26 |
| 22 | Na5 | +27 | Bc8 | +22 |
| 23 | Nc4 | +23 | Nxc4 | +22 |
| 24 | Rxc4 | +24 | Rf7 | +21 |
| 25 | a4 | +22 | h4 | +19 |
| 26 | a5 | +19 | Rb8 | +18 |
| 27 | b4 | +18 | Kg7 | +18 |
| 28 | Rcd4 | +20 | Re7 | +18 |
| 29 | Rd1 | +18 | Bb7 | +20 |
| 30 | Rc1 | +18 | Re5 | +17 |
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 45.9 moves.
Sample game 1 (1/2-1/2)
1. d4 f5 2. c4 g5 3. h4 g4 4. e3 b6 5. Ne2 e6 6. b4 Nf6 7. Nb3 Nc6 8. b5 Ne7 9. Bb4 Qf7 10. Ng3 d6 11. h5 h6 12. Qe2 O-O-O 13. a4 Nh7 14. a5 Ng5 15. Qa2 f4 16. Bg6 Qf6 17. exf4 Qxf4 18. axb6 Nf3+ 19. Kf1 Nh4 20. Kg1 Nf3+ 21. Kf1 Nxd4 22. bxc7 Rd7 23. Kg1 Nf3+ 24. Kf1 Nd4 25. Kg1 Nf3+ 26. Kf1
Sample game 2 (1/2-1/2)
1. d4 f5 2. c4 g6 3. Nab3 b6 4. e3 Nf6 5. Qe2 e5 6. d5 e4 7. Bb4 Rg8 8. Nd4 a5 9. Bc3 Bb7 10. Qc2 Ba6 11. Nb5 Bxb5 12. cxb5 d6 13. O-O Ng4 14. Bxh8 Rxh8 15. Ne2 Qe5 16. g3 Qe7 17. Nd4 h5 18. h3 Ne5 19. h4 Re8 20. Kg2 Ra8 21. b3 Qf6 22. a3 Ra7 23. Qd2 Re7 24. Bc2 Ndf7 25. Rh1 Kd7 26. Rc1 Re8 27. Bd1 Nd3 28. Rc3 Nfe5 29. Be2 Qf7 30. Rd1 Qxd5 31. f4 Ng4 32. Kg1 Nf6 33. Qc2 Ng4 34. Qd2 Nf6 35. Rdc1 Nxc1 36. Rxc1 Qf7 37. Nc6 Raa8 38. Ne5+ Rxe5 39. fxe5 Qd5 40. Qc3 Ne8 41. Rd1 Qc5 42. Bc4 Ke7 43. exd6+ cxd6 44. Rd5 Qxa3 45. Qh8 Kd8 46. Qh7 Qc1+ 47. Kg2 Qb2+
Play it in the CH960 app
Open this page on a phone with the CH960 app installed, or find pair 56 / 819 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): brknqrnb/pppppppp/8/8/8/8/PPPPPPPP/NBNRBQKR w DHbf - 0 1
Mirror twin: White 909 vs Black 131 — a different position (castling squares are fixed), not evaluated by the search.
Current place in the live balance rating: 237.