How to Play Sudoku

A complete guide for beginners and experienced players alike.

What is Sudoku?

Sudoku is a logic-based number puzzle played on a 9x9 grid. The grid is divided into nine 3x3 boxes. Some cells are pre-filled with numbers (called "givens"), and your goal is to fill in the remaining cells following simple rules.

The Three Rules

  1. Rows: Each row must contain the numbers 1 through 9, with no repetition.
  2. Columns: Each column must contain the numbers 1 through 9, with no repetition.
  3. Boxes: Each 3x3 box must contain the numbers 1 through 9, with no repetition.

Getting Started

  • Scanning: Look across rows and down columns to find cells where only one number can go.
  • Crosshatching: Focus on one box at a time. Check which numbers are missing and where they can be placed.
  • Pencil marks: Use the Draft/Note mode to write possible candidates in cells. This helps with harder puzzles.

Tips for Beginners

  • Start with easier difficulty levels to learn patterns.
  • Focus on boxes, rows, or columns that are almost complete.
  • Use the pencil marks feature to track possible numbers.
  • Look for numbers that appear frequently on the board.
  • Don't guess! Sudoku is solvable purely through logic.

Advanced Techniques

As you progress to harder puzzles, you'll need more advanced techniques. Check out our techniques guide for strategies like Naked Pairs, X-Wing, and more.

Ready to Play?

Put your skills to the test with our free online Sudoku puzzles.

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