Sudoku is one of the world's most popular puzzle games, and for good reason. It's challenging, engaging, and great for your brain. If you're new to Sudoku, this guide will teach you everything you need to know to start solving puzzles confidently.
What is Sudoku?
Sudoku is a logic-based number puzzle. The goal is to fill a 9×9 grid with digits from 1 to 9, ensuring that:
- Each row contains all digits from 1 to 9 (no duplicates)
- Each column contains all digits from 1 to 9 (no duplicates)
- Each 3×3 box contains all digits from 1 to 9 (no duplicates)
Basic Sudoku Rules
Before you start solving, it's essential to understand the three fundamental rules:
1. Row Rule
Every row must contain the numbers 1-9 exactly once. You cannot repeat a number in the same row.
2. Column Rule
Every column must contain the numbers 1-9 exactly once. You cannot repeat a number in the same column.
3. Box Rule
Every 3×3 box (there are 9 boxes total) must contain the numbers 1-9 exactly once. You cannot repeat a number within the same box.
Step-by-Step Solving Strategy
Step 1: Look for Obvious Numbers
Start by scanning the grid for cells that can only contain one possible number. Look for rows, columns, or boxes that are almost complete.
Step 2: Use the Process of Elimination
For each empty cell, determine which numbers are already present in its row, column, and box. The numbers that aren't present are your candidates.
Step 3: Look for Single Candidates
If a cell has only one possible number that can fit (based on the row, column, and box rules), that's your answer!
Step 4: Use Pencil Marks
For more challenging puzzles, write small numbers (pencil marks) in cells to track possible candidates. This helps you see patterns and eliminate options.
Step 5: Look for Hidden Singles
A hidden single is a number that can only go in one cell within a row, column, or box, even though other numbers might also be possible in that cell.
Common Beginner Mistakes to Avoid
- Guessing: Sudoku is a logic puzzle. Never guess - always use deduction.
- Not checking all three rules: Always verify row, column, AND box before placing a number.
- Rushing: Take your time. Accuracy is more important than speed when you're learning.
Practice Tips
The best way to improve at Sudoku is to practice regularly. Start with easy puzzles and gradually work your way up to harder difficulties. Our free Sudoku game offers multiple difficulty levels perfect for beginners.
Next Steps
Once you've mastered the basics, you can explore advanced techniques like X-Wing, Swordfish, and Coloring. Check out our Advanced Sudoku Techniques guide when you're ready.