The objective of the game is to fill 9x9 square with digits so that each column, each row, and each of the nine 3×3 smaller squares contains all of the digits from 1 to 9.

The grid is partially completed and provides usually a unique solution. You may play on the screen, you can play after printing the picture on a sheet of paper or you can do both.both.

While playing on the screen the computer helps you by not allowing you to enter wrong digits. For each good entry you get one point and for wrong one point is substracted from your score. However the score below zero is counted but not shown. Enjoy!