CalcuDoku

Flash player support

Due to deprecation of Flash at the end of 2020 we are converting all our games to HTML5 which is supported by all popular browsers. We are planning to complete this process before the end of 2019. In the meantime, in case you have problems enabling Flash on your browser please see these instructions

CalcuDoku tips

General

  • Start with the small blocks and then move to the larger ones.
  • Make small pencilmarks noting which numbers are allowed in the empty squares. This will help narrow down possibilities later on.
  • Always double check before placing a number.
  • Never guess! Only make moves based on logical deductions.

Note: There is only one unique solution for each puzzle.

When solving on paper

  • Use a soft erasable pencil and a high quality eraser.

When playing on a computer

  • Use Preferences options in toolbar for a better personal playing experience.
  • Use pencilmarks to note which numbers are allowed in the empty squares. This will help narrow down possibilities later on.
  • For faster solving, numbers can be placed by pointing mouse on the desired square and then typing with the keyboard.