Opening Explorer showing the move & statistics for the Sicilian Najdorf position using the GM+ online opening book available in the Deep HIARCS Chess Explorer product.


Opening Explorer presents the following statistics against each move:

  • Moves - presented in algebraic notation with move symbols assessing the quality of the moves
  • Games - the number of games where the move has been played
  • Score - the percentage score of the move in practice over those games. The % Score is always given from White's perspective so it is easier for you to compare moves irrespective of which side is to play.
  • Rating - the average Elo rating of the players who played the move
  • Performance - the average performance Elo rating as a result of playing the move, this takes into account the average Elo rating of the opponents played and the performance of the move.
  • Year - the last year that the move was played in practice in the source games.
  • Play% - an assessment of the playability of the move. This only appears on book sources and is context related so for GM books the playability is specific to GMs, whereas in the highly acclaimed HIARCS Tournament book a more narrow assessment of the playability of the absolute best moves is made.


Each of the columns is sortable in both ascending and descending order.