There are three very simple constraints to follow. In a 9 by 9 square Sudoku game:
* Every row of 9 numbers must include all digits 1 through 9 in any order
* Every column of 9 numbers must include all digits 1 through 9 in any order
* Every 3 by 3 subsection of the 9 by 9 square must include all digits 1 through 9
To change between puzzles, click the Reset button at the bottom right hand corner of the Sudoku window and select the new difficulty rating you desire.
Do you sudoku better than the average Australian? Why not share our sudoku puzzles with your friends or family to challenge them?