Sudoku (9x9)
Full-size 9x9 sudoku puzzles. Fill every row, column, and 3x3 box with the numbers 1 to 9.
This tool is for informational and educational purposes only. It is not a substitute for professional financial, medical, legal, or engineering advice. See Terms of Service.
Can't find what you need?
Request a ToolHow to Use Sudoku (9x9)
- Choose a difficulty. Easy removes 35 cells from the complete grid, Medium removes 45, and Hard removes 55. Start with Easy if you are new to full-size sudoku.
- Generate a puzzle. Click "New Puzzle" to create a fresh 9x9 board. Every puzzle has exactly one valid solution.
- Fill in the blanks. Click or tap an empty cell to select it, then type a number from 1 to 9 or tap one of the number buttons below the grid. Each row, column, and 3x3 box must contain every digit from 1 to 9 exactly once.
- Watch for red highlights. If you place a number that conflicts with another cell in the same row, column, or box, both cells turn red. Fix the conflict before moving on.
- Complete the puzzle. When every cell is correctly filled, you will see a congratulations message. Try a harder difficulty next.
Use the Print buttons to create a paper version. "Print with Solution" adds the answer on a second page, ideal for teachers checking student work.
About Sudoku (9x9)
Sudoku is a number-placement logic puzzle invented in the late 1970s and popularized worldwide through newspaper syndication. The standard 9x9 grid is divided into nine 3x3 boxes. The objective is simple: fill every row, column, and box with the digits 1 through 9 so that no digit repeats.
This version is designed for kids ages 8 to 12 who have outgrown the smaller 4x4 and 6x6 grids. Easy mode provides plenty of starting clues for a gentle introduction, while Hard mode challenges experienced solvers. Every puzzle is generated with a guaranteed unique solution, so there is always exactly one correct answer.
Frequently Asked Questions
What age is this sudoku designed for?
This tool is designed for children ages 8 through 12. Younger children should start with the Kids Sudoku tool, which offers smaller 4x4 and 6x6 grids. The Easy difficulty here works well as a bridge for kids who have mastered the smaller grids.
Is this safe for kids?
Yes. The puzzles are created with deterministic algorithms running entirely in your browser. Nothing is uploaded, stored, or shared. There are no external data feeds, no user-generated content, and no chat features.
Does every puzzle have exactly one solution?
Yes. The generator removes cells one at a time and verifies that the puzzle still has a unique solution after each removal. If removing a cell would create multiple valid solutions, that cell stays filled.
Can I print these puzzles for classroom use?
Yes. Click "Print Puzzle" for a clean printable version with empty cells for students to fill in. Click "Print with Solution" to include the answer key on a second page. Generate as many unique puzzles as you need by clicking "New Puzzle" each time.