Enter the known numbers in the Sudoku grid. Only numbers from 1 to 9 are accepted.
Once you have entered everything, click on ‘Check‘. Any invalid digits will now be marked with a red frame. If everything is correct, the numbers you have entered will be marked with a gray frame.
The ‘Solve‘ button will be activated if everything is correct. Press this button to solve the Sudoku puzzle.
The ‘Clear‘ button can be pressed at any time to clear the entire grid.