Hard Sudoku: the challenge for seasoned players – December 6

06/12/2025 - 00:01

If standard sudokus are already a piece of cake for you, it’s time to level up. Here you’ll find the most demanding sudoku challenges. For more hard puzzles, visit the archive of daily hard sudokus.

In a hard sudoku, the clue count is not the only factor; board symmetry, the need for advanced techniques, and the number of candidates per cell also matter. In our grids:

• You’ll need strategies such as X-Wing, Swordfish, Forcing Chains, or Coloring.
• No guessing: every step is logically justified.