Level : Hard

Below the Sudoku board you will find discussions about the techniques used to solve this Sudoku. Use the buttons to the right and left of the board to step through.

Techniques used in this Sudoku:

  1. Box Row Column (see Easy Sudoku)
  2. Triangulation (see Easy Sudoku)
  3. Last Free Cell (see Easy Sudoku)
  4. Notes (see Medium Sudoku)
  5. Obvious Singles (see Easy Sudoku)

This is the strategy we will use:

  1. We start with Box Row Column and Triangulation.
  2. No solutions? Look for Obvious Singles and Last Free Cell.
  3. No solutions? Go back to step 1.
  4. No solutions in steps 1 and 2? Use Notes and look for Obvious Singles.