Blunder Check — Stockfish 19

Paste PGN

Depth Full engine (~99 MB, slow first load) Opening book (skip in-book moves)

Ready. Full Stockfish 19 at depth 16 by default.

Evaluation category thresholds (White’s POV, centipawns)

Symbols in the PGN: +- winning, +/- clearly better, += slightly better, = equal, =+ slightly worse, -/+ clearly worse, -+ losing. Move annotations: □ = only move (PGN $8; requires 2nd best ≥ threshold and a different eval category than best; not if that side is already clearly worse/losing). ? = 1 category worse and ≥ “?” min cp loss. ?? = 2+ categories worse. A variation is written when cp loss ≥ the variation threshold, length ≥ min half-moves when the engine PV is long enough, and the position *before* the move is not already +- or -+. Without ? / ?? / □, the better alternative is marked with $142 (“better is”) on the first move of the variation (UI: ↑ after that move). Every ? / ?? always includes a best-move variation. Quality marks require a change of evaluation category vs the best move.

Equal if |eval| < cp Slightly better/worse from cp Clearly better/worse from cp Winning/losing from cp “?” min cp loss cp Only move (□) if 2nd best ≥ cp worse Variation if cp loss ≥ cp Variation min length half-moves

Move analysis