Interactive King Opposition & Square-of-the-Pawn Visualizer
Stop counting move-by-move in time trouble. Reposition the White Pawn, White King, and Black King on the 8×8 board to visualize the Square of the Pawn and spot Direct, Distant, and Diagonal Opposition instantly.
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Frequently Asked Questions
What is the Rule of the Square of the Pawn?
Draw a diagonal from the passed pawn to the promotion rank to form a square. If the defending King stands inside that square — or can step into it on its turn — it catches the pawn without assistance. Note that a pawn on the 2nd rank projects its square from the 3rd rank because of its initial two-square advance!
Who holds the opposition when two Kings face each other?
When Kings stand on the same file, rank, or diagonal separated by an odd number of squares (1, 3, or 5 squares between them), the player who does NOT have to move holds the opposition, forcing the rival King to give way.
Why are Distant and Diagonal Opposition important in open endgames?
Distant opposition (3 or 5 squares apart on the same file/rank) and Diagonal opposition serve as stepping stones: by maintaining same-color square parity, you convert distant opposition into direct opposition as the Kings approach.
What do the blue OPP, DIAG, and DIST badges on the board show?
They highlight every legal single-square move available to the side-to-move's King that immediately seizes Direct (OPP), Diagonal (DIAG), or Distant (DIST) opposition against the rival King.