Sudoku is a Japanese game of logic.

This implementation in Java generates unique random puzzles at three difficulty levels, with or without symmetry. The application will also solve most Sudokus found in newspapers or magazines, except those requiring X-Wing, Swordfish and other more advanced solving algorithms, which have not been implemented here.

How to play
  • Click 'New Sudoku' to generate a puzzle of the desired difficulty.
  • Fill in the grid so that all the letters from 1 to 9 appear exactly once within each...

    * Horizontal row,

    * Vertical column, and

    * 3x3 box.

  • Click 'Check' to see if you're done, or 'Solve' to get the solution.