White 295 vs Black 139
White starts from setup 295 (QNBRKRNB), Black from setup 139 (NRQNBKRB). 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 #295 Q N B R K R N B
King on the e-file, rooks on d, 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 295 gives White +0.19 (Morozov Balance Index, 400M nodes).
Black: setup #139 N R Q N B K R B
King on the f-file, rooks on b, g, queen on the c-file; one bishop starts in a corner; the knights start away from the centre. Castling follows the Chess960 rule: king and rook end on the classical squares. In ordinary symmetric play setup 139 gives White +0.28 (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 57.
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 -11 and +23 cp before settling — a reminder that quick engine checks overstate imbalances, and why the ladder goes deep.
For comparison, in symmetric play setup 295 gives White +0.19 and setup 139 gives White +0.28: 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 Nf3, and 3 first moves are within 10 cp of it.
Along the engine's main line (30 moves) the largest swing was 80 cp (around move 18), ending at -21 cp — the position stays playable for both sides.
Engine self-play agrees: 10 games, White won 0, drawn 10, Black won 0 (White scored 50.0%).
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 | 15 | +23 | 1. Nf3 c5 2. d4 cxd4 3. O-O Ne6 4. c3 dxc3 |
| S1 | 500 000 | 19 | -3 | 1. Nf3 c5 2. d4 cxd4 3. Nxd4 Nc7 4. b3 Nce6 |
| S2 | 2 000 000 | 25 | -3 | 1. Nf3 d6 2. O-O b5 3. d4 Nb6 4. g3 O-O |
| S3 | 8 000 000 | 32 | -11 | 1. Nf3 b5 2. g3 d6 3. b3 O-O 4. O-O Nb6 |
| S4 | 32 000 000 | 38 | -3 | 1. Nf3 d6 2. d4 b5 3. O-O Nb6 4. Rfe1 O-O |
| S5 | 128 000 000 | 49 | 0 | 1. Nf3 d6 2. d4 b5 3. O-O Nb6 4. Rfe1 O-O |
| S6 | 400 000 000 | 52 | 0 | 1. Nf3 d6 2. d4 b5 3. O-O Nb6 4. Rfe1 O-O |
| S7 | 800 000 000 | 54 | 0 | 1. Nf3 d6 2. d4 b5 3. O-O Nb6 4. Rfe1 O-O |
| S8 | 1 600 000 000 | 57 | 0 | 1. Nf3 d6 2. d4 b5 3. O-O O-O 4. b3 Nb6 |
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 | -1 |
| 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: +1
- Lc0 0.32.1: 0
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 +44, Black +21, difference +23. 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, 10 draws, 0 Black wins, White scored 50.0%.
Best first moves
The 3 best first moves for White, searched together at 400 000 000 nodes.
| # | Eval, cp | Depth | Main line |
|---|---|---|---|
| 1 | +7 | 45 | 1. Nf3 d6 2. O-O b5 3. d4 O-O 4. b3 Nb6 5. Rfe1 f5 |
| 2 | +4 | 44 | 1. d4 d6 2. Nf3 b5 3. O-O O-O 4. b3 Nb6 5. Rfe1 f5 |
| 3 | -2 | 44 | 1. g3 d6 2. Nf3 b5 3. d4 Nb6 4. O-O O-O 5. e4 Bd7 |
Main-line play-out
30 moves, 5 000 000 nodes per half-move. Largest |evaluation| 80 cp, mean 40.8 cp, final -21 cp.
| # | White | cp | Black | cp |
|---|---|---|---|---|
| 1 | Nf3 | -8 | d6 | -2 |
| 2 | d4 | -3 | b5 | -11 |
| 3 | O-O | -10 | Nb6 | -4 |
| 4 | Rfe1 | +1 | c5 | -9 |
| 5 | g3 | -12 | cxd4 | -20 |
| 6 | Nxd4 | -19 | g5 | -28 |
| 7 | b3 | -30 | f5 | -43 |
| 8 | Nc3 | -33 | Rg6 | -41 |
| 9 | e4 | -38 | f4 | -35 |
| 10 | Nce2 | -36 | Bd7 | -44 |
| 11 | Bb2 | -32 | Nf7 | -45 |
| 12 | Bg2 | -37 | Bh3 | -37 |
| 13 | Nf5 | -40 | Bxg2 | -50 |
| 14 | Kxg2 | -43 | Be5 | -37 |
| 15 | Kh1 | -52 | Nd7 | -54 |
| 16 | f3 | -48 | Nf6 | -50 |
| 17 | a4 | -53 | bxa4 | -55 |
| 18 | Bxe5 | -80 | dxe5 | -70 |
| 19 | Qxa4 | -80 | g4 | -80 |
| 20 | Ng1 | -73 | a5 | -72 |
| 21 | Qxa5 | -74 | fxg3 | -66 |
| 22 | Nxg3 | -65 | Qxc2 | -63 |
| 23 | Rc1 | -72 | Qxb3 | -73 |
| 24 | Rf1 | -60 | Qe6 | -51 |
| 25 | fxg4 | -51 | Rxg4 | -45 |
| 26 | Qc7 | -46 | Re8 | -49 |
| 27 | Rc6 | -33 | Qa2 | -30 |
| 28 | Nf3 | -26 | Rf4 | -34 |
| 29 | Rcc1 | -28 | Qe6 | -24 |
| 30 | Qc4 | -24 | Qxc4 | -21 |
Engine self-play
10 games at 500 000 nodes per move: White won 0, drawn 10, Black won 0 — White scored 50.0%. Average length 38.1 moves.
Sample game 1 (1/2-1/2)
1. d4 b5 2. b3 Nb6 3. Nf3 d6 4. g3 O-O 5. O-O f5 6. Nbd2 g6 7. c3 c5 8. e4 Bc6 9. Rfe1 c4 10. bxc4 bxc4 11. exf5 Qxf5 12. Re2 Nd5 13. Rde1 Bg7 14. Bb2 Bh6 15. Bc1 Qh5 16. Bg2 Nf6 17. Nh4 Bxg2 18. Nxg2 Bxd2 19. Bxd2 e5 20. Qc1 Nf7 21. f3 Qh3 22. Qc2 Qd7 23. Nh4 Nh5 24. Qe4 Nf6 25. Qc2 Nh5 26. Qe4 Rbc8 27. Ng2 a6 28. Rf2 Qb5 29. Qh4 Ng7 30. Ne3 exd4 31. Qxd4 Ne6 32. Qd5 Neg5 33. Kg2 Rc5 34. a4 Qd7 35. Qd4 Ne5 36. Ng4 Nxg4 37. Qxg4 Qxg4 38. fxg4 Rxf2+ 39. Kxf2 Kf7 40. h4 Ne6 41. Rb1 Rd5 42. Rb7+ Kf6 43. g5+ Kf5 44. Ke2 Kg4 45. Rxh7 Re5+ 46. Kd1 Kxg3 47. Rh6
Sample game 2 (1/2-1/2)
1. g3 O-O 2. b3 g6 3. Bb2 Bxb2 4. Qxb2 d6 5. Nf3 b5 6. d4 c5 7. O-O Nb6 8. e4 cxd4 9. Qxd4 Qc7 10. Nc3 Rc8 11. Nd5 Nxd5 12. exd5 e5 13. dxe6 Nxe6 14. Qa1 Bc6 15. Rfe1 Ba8 16. Re2 Qc3 17. Qxc3 Rxc3 18. Ne1 Bxh1 19. Kxh1 Rd8 20. Kg2 Kf8 21. Rd5 Rc5 22. Red2 Ke7 23. c3 Rxd5 24. Rxd5 a6 25. Nc2 Kd7 26. Rd3 Rc8 27. Ne3 Nc5 28. Rd4 Ne6 29. Rd3 Nc5 30. Rd4 Ne6
Play it in the CH960 app
Open this page on a phone with the CH960 app installed, or find pair 295 / 139 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): nrqnbkrb/pppppppp/8/8/8/8/PPPPPPPP/QNBRKRNB w DFbg - 0 1
Mirror twin: White 370 vs Black 817 — a different position (castling squares are fixed), not evaluated by the search.