This is the Sudoku that launched the craze.

From Nikoli, the Japanese company that invented the game, this  bestselling calendar features puzzles that are exceptional for their elegance and perfect balance of toughness and solvability.

Not generated by computer but thoughtfully crafted by hand, each day's challenge is like a one-on-one match with its expert creator.

THE ORIGINAL SUDOKU calendar features two easier puzzles each weekend. with increasing difficulty over the course of the week. In case you find yourself hopelessly stumped, solutions are printed on the reverse side of each page. 

Introducing new eco-friendly cardboard backer and larger page size! Printed on FSC-certified paper.
  This is the Sudoku that launched the craze. From Nikoli, the Japanese company that invented the game, this 1.7-million-copy bestselling calendar features puzzles that are exceptional for their elegance and perfect balance of toughness and solvability. Thoughtfully crafted by hand, not generated by computer, each day's challenge is like a one-on-one match with its expert creator. THE ORIGINAL SUDOKU calendar features two easier puzzles each weekend. with increasing difficulty over the course of the week. In case you find yourself hopelessly stumped, solutions are printed on the reverse side of each page. Introducing new eco-friendly cardboard backer and larger page size! Printed on FSC-certified paper.