Sudoku, also known as Number Place, is a logical number-placement puzzle with a grid and numbers. Cells in the grid must contain a digit so that each row, each column and each block contains all of the digits 1-9 once. Variants Choose from different Sudoku variants: Sudoku Standard, Sudoku X, Sudoku Hyper, Sudoku Hyper X, Latin Square and Latin Square X. Sizes Choose from different sizes: 6x6, 9x9, 12x12 and 16x16. Difficulty Choose from 5 levels of difficulty for all Sudoku variants. For a Sudoku Standard 9x9 you can choose from an extra level of difficulty which require the usage of advanced solving techniques. Notes Use the notes function to manage all candidates for all cells. These will be eliminated automatically when placing a digit. But you can also eliminate candidates manually. This is very useful if you are using advanced solving techniques. Mistakes Use the mistakes function to see all incorrect digits. This is useful if you are stuck, but also to prevent to get stuck. Save Every Sudoku can be saved, so you do not lose any progress. There is no limitation on how many Sudokus can be saved. Once a saved Sudoku is completed, it will be automatically deleted. Every Sudoku is randomly generated. This provides an almost infinite amount of different Sudokus. Because Sudokus are randomly generated there might be a slight variation in the time required to do so. Note: Sudoku Hyper (X) is not available for size 6x6.