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Which first move is best — and why

Chess960 has no opening theory: 960 setups, no books, and the very first move is already a question nobody has answered for you. Every first move of every setup has been evaluated in advance — play the one you think is best, and see what it is worth.

Setup no. 489 — your move

Play the move you think is best.

How a move is judged

By what it LOSES against the best move, not by its place in a top three. The reason is measured, not assumed: the top of the list sticks together — in a typical setup about five first moves out of twenty are indistinguishable — and the order inside that cluster changes between search budgets, while the loss does not.

So "as good as the best" is a band, not a single square. Inside that band the trainer says so plainly instead of correcting you: being told off for a move the engine itself cannot tell apart from the best one teaches nothing.

Loss against the best move Verdict
≤ 0.20 As good as the best — indistinguishable at this budget
0.20 – 0.50 Weaker, but perfectly playable
0.50 – 1.00 Inaccuracy
1.00 – 3.00 Mistake
> 3.00 Serious mistake

What the numbers are

  • Engine Stockfish 17.1, one thread, a fixed budget of 100 million nodes per setup, evaluation taken from the last COMPLETED iteration — the run reproduces bit for bit.
  • ALL legal first moves are evaluated, not just the strongest few: whatever you play, the answer comes from the table — instantly, offline and identically on every device.
  • For each move the engine's main line is kept for eight half-moves: that is the "where it would lead" line under the verdict.

Table generated 2026-10-05.

Open data · Methodology · The whole table as JSON

Why the first move

In classical chess the first move comes from books. In Chess960 there are no books: a setup you have never seen appears on the board and the clock starts. Deciding there, from scratch, is the skill this trainer builds — and it is the one skill classical opening study cannot give you.

The explanation is assembled from facts that can be checked on the board — occupying the centre, developing a piece, freeing a bishop locked in by its own pawns (a Chess960 disease), making castling possible — plus the engine's own main line. It is not a grandmaster's commentary, and we do not pretend otherwise.

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