🧩 Sudoku Rules Explained: A Complete Beginner's Guide

Sudoku is a logic-based number puzzle that has become a global favorite for sharpening the mind and passing time. It looks like math, but it’s all about logic, patterns, and problem-solving. If you're new to Sudoku, don’t worry—this guide will walk you through the rules step by step.

1. What Is Sudoku?

Sudoku is played on a 9x9 grid, divided into nine 3x3 subgrids (also called "boxes" or "regions"). Some cells already contain numbers at the start, and your task is to fill in the remaining cells following the rules.

2. The Basic Rules of Sudoku

Each row must contain the numbers 1 through 9 with no repeats.
Each column must also contain the numbers 1 through 9 with no repeats.
Each 3x3 box must contain the numbers 1 through 9 with no repeats.

Important: Numbers cannot be repeated within any row, column, or box, but they can appear in the same position in different rows/columns/boxes.

3. Starting the Puzzle

You start with a partially filled grid. The difficulty of the puzzle depends on how many numbers are pre-filled and their placement. Easier puzzles give more clues; harder puzzles provide fewer and rely on more complex logic.

4. Strategies to Solve Sudoku

Scan for Obvious Numbers

Look for rows, columns, or boxes that are nearly complete, then fill in the missing number(s) by process of elimination.

Use Pencil Marks

In tougher puzzles, write down all possible numbers for a cell in small print. As you progress, you'll be able to eliminate some of these options.

Look for Hidden Singles

Sometimes a number can only go in one possible cell in a row, column, or box—even if other options aren’t immediately obvious.

5. What’s Not Allowed

You cannot guess! Sudoku is a logic puzzle—every number must be placed with certainty. Guessing can ruin your solution if you're wrong, especially in more complex puzzles.

6. Variations of Sudoku

There are many variants of Sudoku for added challenge, such as:

Mini Sudoku: Played on a 6x6 or 4x4 grid.
Diagonal Sudoku: Diagonals must also contain 1–9 with no repeats.
Samurai Sudoku: Multiple overlapping Sudoku grids.

7. Winning the Game

You win when the entire grid is correctly filled according to the rules. There is only one unique solution per standard puzzle.

Final Thoughts

Sudoku is more than just a puzzle—it’s a brain workout. With practice, your pattern recognition and problem-solving skills will improve dramatically. Start with easy puzzles and gradually move to harder levels as your skills grow.

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