Variant playground

Diagonal Sudoku

Diagonal Sudoku uses the Sudoku X rule: both long diagonals must contain every digit once in addition to rows, columns, and boxes.

Related Sudoku variants

These pages cover related formats and alternate names for this puzzle type.

Sudoku X Sudoku X adds both long diagonals as extra regions, so every digit must appear once on each diagonal as well as in every row, column, and box. Killer Sudoku Killer Sudoku combines classic regions with arithmetic cages. Use the cage totals to narrow candidates before placing digits. Samurai Sudoku Samurai Sudoku links five classic grids together, with shared overlap boxes that must satisfy both grids. Sudoku Variants Browse Sudoku X, Killer Sudoku, Mini Sudoku, Samurai Sudoku, and related formats.