What Sudoku types are supported?
Sudoku Spoiler supports over 50 Sudoku variants. All variants share the basic Sudoku rule: each row and column contains each character exactly once. They differ in the additional constraints described below.
Sudoku — The classic puzzle. Each row, column, and box contains each number exactly once. Also available as Alphabet Sudoku (with letters), Wordoku (with a custom set of letters), or Hexadoku (16x16 with hexadecimal digits). Larger grids (12–16) also accept mixed input combining numbers and letters.
Sudoku X — Also called Diagonal Sudoku. Classic Sudoku rules, plus both main diagonals must contain each character exactly once.
Irregular Sudoku — Also called Jigsaw, Chaos, or Nonomino Sudoku. Instead of rectangular boxes, the grid is divided into irregular regions. Drag and drop cells to define custom regions. Also available as Toroidal Sudoku, where regions wrap around the edges of the grid.
Irregular Sudoku X — Irregular Sudoku combined with the diagonal constraint of Sudoku X.
Hyper Sudoku — Also called NRC Sudoku or Windoku. Classic Sudoku rules, plus four extra shaded regions that must each contain every character exactly once.
Hyper Sudoku X — Hyper Sudoku combined with the diagonal constraint.
Extra Region Sudoku — Classic Sudoku rules, plus additional highlighted cells that form extra regions. Each extra region must contain every character exactly once. Variants include Girandola, Center Dot, Asterisk, Percent, and NU Hyper Sudoku — each with a different pattern of extra cells.
Odd-Even Sudoku — Also called Sudoku Tanto. Classic Sudoku rules, plus cells are marked as odd or even, restricting which numbers can go where. Only accepts numbers.
Offset Sudoku — Also called Disjoint Groups or DG Sudoku. Classic Sudoku rules, plus cells in the same position within their box must all be different.
S-doku — Also called Steenhuis Sudoku. Classic Sudoku rules with an additional constraint based on a specific pattern of extra regions.