Sudoku Generator

Generate, play and print unique-solution Sudoku puzzles, including 4-up worksheets.

About this tool

Generate, solve and play 9×9 Sudoku puzzles. Difficulty controls how many cells start blank; the generator only removes a cell if the puzzle still has a unique solution.

Buttons

  • New puzzle: regenerate.
  • Hint: fill one random unknown cell with the correct digit.
  • Check: report wrong / blank cells (wrong values are also coloured red as you type).
  • Reveal solution: fill the entire grid.