Sudoku Variants

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. Diagonal Sudoku Diagonal Sudoku uses the Sudoku X rule: both long diagonals must contain every digit once in addition to rows, columns, and boxes. Killer Sudoku Killer Sudoku combines classic regions with arithmetic cages. Use the cage totals to narrow candidates before placing digits. Sum Sudoku Sum Sudoku uses Killer Sudoku cage totals to narrow candidates before filling the classic Sudoku grid. Mini Sudoku Mini Sudoku keeps the same logic in a compact grid, making it useful for fast practice or newer players. 4x4 Sudoku 4x4 Sudoku keeps the core logic compact for quick practice, newer players, and short puzzle breaks. 6x6 Sudoku 6x6 Sudoku adds more variety while staying faster than a full 9x9 board. Samurai Sudoku Samurai Sudoku links five classic grids together, with shared overlap boxes that must satisfy both grids. Five Grid Sudoku Five Grid Sudoku is the Samurai format: five linked boards with overlap boxes that connect the puzzle.