Master X-Sudoku rules where both main diagonals must also contain digits 1-9. Learn strategies for this challenging Sudoku variant with extra constraints.

Follow all classic Sudoku rules, plus both main diagonals (top-left to bottom-right and top-right to bottom-left) must also contain digits 1-9 without repetition. This adds an extra layer of complexity to the classic puzzle.
Same as Classic: Each horizontal row must contain all digits from 1 to 9 without repetition.
Same as Classic: Each vertical column must contain all digits from 1 to 9 without repetition.
Same as Classic: Each 3×3 box must contain all digits from 1 to 9 without repetition.
Both main diagonals must contain digits 1-9 without repetition. This creates additional constraints that make the puzzle more challenging.
Start with classic Sudoku techniques first - rows, columns, and boxes.
Check both diagonals frequently as they add extra constraints that can help you solve faster.
Numbers on the diagonals eliminate more possibilities in their row, column, box, AND diagonal.
The center cell (row 5, column 5) is part of both diagonals and has the most constraints.
Download today's free printable X-Sudoku puzzle. Classic rules plus both main diagonals must contain digits 1-9.
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