How to Play Sudoku

Sudoku is a number-placement puzzle played on a 9×9 grid. The goal is to fill every cell with a digit from 1 to 9 so that each row, each column, and each of the nine 3×3 boxes contains all the numbers from 1 to 9 exactly once.

The Basic Rules

• Use only the numbers 1 through 9.
• Each number can appear only once in every row.
• Each number can appear only once in every column.
• Each number can appear only once in every 3×3 box.

Getting Started

A sudoku puzzle starts with some numbers already filled in. These are called "givens." A well-made puzzle has exactly one solution that can be reached through logic alone—you never need to guess.

Beginners should look for rows, columns, or boxes that are almost complete. If a row already has the numbers 1 through 8, the empty cell must be 9. That is the simplest form of solving.

Simple Solving Tips

• Scan for singles: Look for a number that is missing from a row, column, or box and can only go in one cell.
• Work box by box: Focus on one 3×3 box at a time instead of scanning the whole grid.
• Pencil in candidates: Write small notes of possible numbers in empty cells to spot patterns.
• Check rows and columns together: A number needed in a box might be blocked from some cells by the same number in a row or column.

Difficulty Levels

Our sudoku generator offers four difficulty levels. Easy puzzles have more givens and simple patterns, making them great for kids or first-time players. Medium and hard puzzles require more advanced techniques. Expert puzzles are designed for seasoned solvers who want a serious challenge.

Make Your Own Sudoku Worksheets

Ready to practice? Head back to our free Sudoku Generator and create a printable puzzle pack in seconds. Choose the difficulty, the number of puzzles, and how they fit on the page, then print or save as PDF.