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Online Sudoku

Play free online Sudoku with 4 difficulty levels, auto-save, and notes mode. Improve your logic and memory with this brain training game.

Sudoku

How to Play Sudoku

Sudoku is a classic logic-based puzzle game played on a 9x9 grid, divided into nine 3x3 subgrids.

🎯 Objective

Fill the grid so that every row, column, and 3x3 box contains the digits 1 through 9 without repetition.

🎮 Controls

  1. Select: Click any cell to select it.
  2. Input: Use the number pad or your keyboard (1-9).
  3. Erase: Click the same number again to remove it, or use the "Erase" button.

📝 Key Feature: Notes Mode

Don't guess! Use notes to track candidates.

  • Toggle ON: Click the "Notes" button.
  • Mark Candidates: Enter numbers to add them as small notes in the cell. You can mark multiple numbers (e.g., 1, 5, 9).
  • Toggle OFF: When you are sure of the answer, turn Notes OFF and enter the final number.

🧠 Benefits of Sudoku

  • Logic Skills: Improves logical thinking and problem-solving skills.
  • Memory: Enhances short-term memory and concentration.
  • Brain Health: Keeps your brain active and may reduce the risk of cognitive decline.
  • Stress Relief: Focusing on logic helps calm the mind and reduce anxiety.
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