Play Windoku Online Free

Play Windoku (Hyper Sudoku) online for free. Four extra 3×3 windows add additional constraints to classic Sudoku. Also known as NRC Sudoku.

▶ Play Windoku (Hyper Sudoku) — Free
🟢 Easy 🟡 Medium 🟠 Hard 🔴 Expert

How to Play Windoku (Hyper Sudoku)

  1. Standard Sudoku rules apply.
  2. Four shaded 3×3 windows are overlaid on the grid.
  3. Each window must also contain digits 1-9 with no repeats.
  4. This adds four extra 'boxes' to reason about.
💡 Pro Tip
Cells inside windows have an extra constraint, making them easier to solve first. Work from the windows outward.

Frequently Asked Questions

Is Windoku the same as NRC Sudoku or Hyper Sudoku?

Yes — Windoku, NRC Sudoku, and Hyper Sudoku all refer to the same variant with four extra 3×3 window regions.

How does Windoku compare to X-Sudoku?

Both add extra constraint regions to classic Sudoku, but Windoku adds four 3×3 windows while X-Sudoku adds the two main diagonals.

Try More Puzzle Modes

🧩X-Sudoku (Diagonal Sudoku) 🧩Classic Sudoku 🧩Jigsaw Sudoku
▶ Play Windoku (Hyper Sudoku)