sudokly

Hyper Sudoku

Classic sudoku with four extra 3×3 regions to satisfy.

Medium00:000

What hyper sudoku feels like.

Hyper sudoku. also called windoku. adds four extra 3×3 regions inside the grid, offset from the standard boxes. Each of those four extra regions must also contain digits 1 through 9 exactly once. The added constraints tighten the puzzle considerably.

Rules

  1. Standard 9×9 sudoku rules apply.
  2. Four extra 3×3 regions at rows 2-4 and 6-8, columns 2-4 and 6-8, each contain digits 1-9 exactly once.
Key rule
Four extra 3×3 regions also contain 1-9
Difficulty range
Medium to expert
Tips
  • The cells inside the four extra regions are heavily constrained. start there.
  • A digit placed in the centre cell of the grid (5,5) lies in two regions at once if your variant uses the central hyper-region.
  • Pencil marks are nearly mandatory for hyper sudoku above easy.

Hyper Sudoku FAQ

Is hyper sudoku the same as windoku?
Yes. They're identical: four extra 3×3 regions in addition to the standard nine.
How are the extra regions placed?
At rows 2-4 and 6-8, columns 2-4 and 6-8. They overlap the standard boxes but never coincide with them.
Is hyper sudoku harder than classic?
Roughly equivalent at the same clue count. the extra constraints add information but also create more inter-region eliminations.
Are these always unique?
Yes. Every Sudokly hyper puzzle has exactly one solution.
Why is it called hyper?
The original Japanese name is more literal. 'extra region sudoku'. 'Hyper' came from English-language publications and stuck.