# Sudoku Variant

From

Jump to navigationJump to search**Sudopedia**, the Free Sudoku Reference GuideThere are numerous ways to vary the basic Sudoku format. Yet, only a few variations have developed a loyal group of supporters. Most variations are regarded as a curiosity.

## Variant Types

There are many ways to vary a Sudoku. Here are only a few examples:

- Change the size
- 2x2 Shi Doku
- 4x4
- 5x5
- 6x6
- 12x12
- 16x16
- 25x25

- Replace boxes by other shapes
- Rectangles
- 2x3
- 3x4

- Jigsaw Sudoku

- Rectangles
- Add extra constraints (Sudoku-X, Windoku, Asterisk, Girandola, Center Dot, Even-Odd, Non-Consecutive, Consecutive Puzzle, Sudoku-DG)
- Replace givens by alternative clues (Killer Sudoku, Greater Than)
- Replace digits by letters, symbols or images (YourDoku, Wordoku, Picture Sudoku)
- Merge several constituent puzzles (Gattai, Samurai, Clueless)
- Use non-rectangular cells (Hanidoku)

To complicate things, a puzzle maker can combine several of these alterations.

## Popular Variants

These often appear in newspapers or feature in dedicated puzzle books.

- Killer Sudoku | Killer | Sum-Sudoku | Samunamupure
- Given numbers are replaced by cages labeled with the sum of the digits inside the cage. This is by far the most popular Sudoku variation.

- Jigsaw Sudoku | Nonomino | Squiggly | Irregular Sudoku
- 3x3 boxes are replaced by regions with an irregular shape.

- Sudoku-X
- The 2 diagonals also require digits 1 through 9.

- Windoku | Hypersudoku | Sudoku Hyper | NRC-Sudoku
- There are 4 additional 3x3 boxes in the grid which must also contain digits 1 through 9.

- Samurai | Gattai-5
- A puzzle with 5 partially overlapping Sudoku grids.

## Common Variants

There appear occasionally in newspapers, but have dedicated websites and appear on a regular basis in Sudoku variant books.

- Clueless
- A puzzle with 9 Sudoku grids where the center nonets form a 10th Sudoku grid.

- Flower Sudoku
- A puzzle where 4 Sudoku grids each overlap 6 boxes of a central Sudoku grid.

- Hanidoku
- A puzzle with hexagonal cells that must contain a consecutive series of digits.

- Greater Than
- A puzzle where the given digits are replaced by greater-than signs.

- Consecutive Puzzle
- A puzzle where any 2 adjacent cells containing consecutive digits are marked on the border between the cells.

- Non-Consecutive
- A puzzle where 2 adjacent cells cannot contain consecutive digits.

## Other Variants

These variants are less common.

- Sudoku3D
- A 3D implementation of a classic sudoku. Sudoku3D is a single puzzle on a surface of 4x4x4 cube.

- Center Dot
- An ordinary Sudoku with an extra constraint involving the center square of each box.

- Asterisk
- An ordinary Sudoku with an extra constraint which looks like an asterisk.

- Sukaku
- An ordinary Sudoku, except that the starting position contains pencilmarks instead of givens.

- Sumo | Gattai-13
- A puzzle with 13 partially overlapping Sudoku grids.

- Shaolin | Gattai-25
- A puzzle with 25 partially overlapping Sudoku grids.

- Kansuko
- A 3x9 grid with a sum column as an additional constraint.

## External Links

- Sudoku Variants wiki at the World Puzzle Federation web site