Master diagonal visualization by tracing bishop paths across the board. Understanding which squares share diagonals helps you spot attacks and defenses without seeing the pieces.
Pro tip: The bishop always moves diagonally and stays on its starting color.
60s
Leaderboard
About Bishop Movement
Reading diagonals without a board
You get a bishop on a square and 60 seconds to mark every square it attacks. It is the most direct way to fix the one fact that makes diagonals hard: unlike ranks and files, a diagonal changes length as it moves across the board. The long a1-h8 diagonal holds eight squares, its neighbour holds seven, and the corner ones hold two. Players who never internalise that keep expecting a bishop to reach further than it does, or miss that it already reaches further than they thought.
The shortcut worth learning is that a bishop on a centre square (d4, e4, d5, e5) sees thirteen squares while one in a corner sees seven, which is the whole argument for centralising bishops compressed into two numbers. The second is that both of a bishop's diagonals share its square colour, so half the board can be ruled out before you start counting. Once the attack map is instant, put it under pressure with the bishop maze, which asks for shortest paths rather than reachable squares, or test the same relationship from the other side with the diagonals drill. For how diagonal vision feeds full blindfold calculation, see the chess visualization guide.