White 60 vs Black 340

The two setups

White: setup #60 N B N R Q K B R

King on the f-file, rooks on d, h, queen on the e-file; no 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 60 gives White +0.22 (Morozov Balance Index, 400M nodes).

Black: setup #340 N B B R K Q R N

King on the e-file, rooks on d, g, queen on the f-file; no 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 340 gives White +0.29 (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 agreed early: from 100 thousand to 128 million nodes the evaluation never left ±14 cp.

For comparison, in symmetric play setup 60 gives White +0.22 and setup 340 gives White +0.29: 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 c3, and 2 first moves are within 10 cp of it.

Along the engine's main line (14 moves) the evaluation stayed within ±21 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 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.

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.

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: +15

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 +92, Black +60, difference +32. 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.

Main-line play-out

14 moves, 5 000 000 nodes per half-move. Largest |evaluation| 21 cp, mean 7.2 cp, final 0 cp.

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 38.5 moves.

1. c3 f5 2. h4 Qf6 3. e4 d6 4. exf5 Bxf5 5. Bxf5 Qxf5 6. Rh3 Nb6 7. d4 O-O 8. Qe2 Nf7 9. Nc2 c6 10. Ne3 Qc8 11. Bh2 e5 12. Kg1 exd4 13. cxd4 Rde8 14. Qc2 Nh6 15. Qb3+ Kh8 16. h5 Nd7 17. Nd3 d5 18. Bxb8 Qxb8 19. Re1 Re4 20. Qc3 Rfe8 21. a4 Qd6 22. a5 a6 23. Rf3 Kg8 24. g3 Nf7 25. Kg2 Qe6 26. Qb3 Ng5 27. Rf5 h6 28. Nf4 Rxf4 29. Rxf4 Qh3+ 30. Kg1 Qxh5 31. Kg2 Qh3+ 32. Kg1 Qh5 33. Kg2 Qh3+ 34. Kg1

1. c3 f5 2. e4 c6 3. f3 Nb6 4. exf5 g6 5. f6 Qxf6 6. Nd3 Nf7 7. Qe2 Nd5 8. Bd4 Qe6 9. Qxe6 dxe6 10. O-O-O b6 11. Bf2 c5 12. Bg3 e5 13. Rhe1 Nf4 14. Nxf4 exf4 15. Bf2 Ne5 16. d4 cxd4 17. Bxd4 Nc6 18. Nb3 Bf5 19. Be4 Bxe4 20. Rxe4 g5 21. Bf2 g4 22. fxg4 Rxg4 23. g3 Ne5 24. Nd4 fxg3 25. Rxg4 Nxg4 26. Bxg3 Bxg3 27. hxg3 e5 28. Nc6 Rxd1+ 29. Kxd1 a5 30. Ke2 Kd7 31. Na7 e4 32. Nb5 Ke6 33. Nd4+ Ke5 34. Nc6+ Kd6 35. Nd4 Nf6 36. Nc2 Nh5 37. Kf2 Kc5 38. Ne3 b5 39. Nf5 Kd5 40. Ne3+ Ke5

Play it in the CH960 app

Open this page on a phone with the CH960 app installed, or find pair 60 / 340 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): nbbrkqrn/pppppppp/8/8/8/8/PPPPPPPP/NBNRQKBR w DHdg - 0 1

Mirror twin: White 908 vs Black 334 — a different position (castling squares are fixed), not evaluated by the search.

Current place in the live balance rating: 259.