Unlike level 3 or above sudoku games, level 2 games on this page do not need to use the divide-and-conquer technique. They can be solved with simple logic reasoning. Yet, many of them are very challenging.

Level 1 sudoku games on this website only need two basic techniques to solve completely. At every step, one aquare can be solved.

• 1. For a square, if eight of nine numbers cannot be placed there, then the only left number has to be there.
• 2. For a link (that is a row, a column, or a block), if a number can be placed only in one of the nine squares, then the number has be in that square.