How do I enter a Sudoku puzzle?
Enter the known numbers into the corresponding cells and leave unknown cells empty. You can then start the solver to complete the puzzle.
Games
Sudoku Solver
Solve Sudoku puzzles online, detect invalid entries and download the completed grid as PNG, JPG or PDF directly in your browser.
Tool
Sudoku Solver
Solve Sudoku puzzles online, detect invalid entries and download the completed grid as PNG, JPG or PDF directly in your browser.
This tool runs in your browser. Your input is processed locally and is not uploaded.
About this Tool
Enter or paste the known numbers from a standard 9 × 9 Sudoku puzzle and let the solver complete the remaining cells. The tool validates rows, columns and 3 × 3 boxes, detects conflicting entries and determines whether the puzzle has no solution, one solution or multiple solutions. Completed grids can be downloaded as PNG, JPG or PDF, with all processing kept locally in your browser.
Examples
- Solve an incomplete 9 × 9 Sudoku grid
- Check a puzzle for conflicting numbers
- Download a completed grid as PNG, JPG or PDF
Frequently Asked Questions
Can the solver detect invalid Sudoku entries?
Yes. It checks for duplicate numbers in rows, columns and 3 × 3 boxes before attempting to solve the puzzle.
What happens if the Sudoku has no solution?
The solver reports that the puzzle cannot be completed when the entered clues lead to a contradiction or no valid solution exists.
Can a Sudoku have more than one solution?
Yes. A puzzle with too few or poorly selected clues may allow multiple valid solutions. The solver can report this instead of presenting the puzzle as uniquely solvable.
Does the Sudoku solver show calculation steps?
The tool can show recorded solver placements, including search branches. These are solver progress details, not a claimed human deduction path.
Can I download the completed Sudoku?
Yes. After solving, the completed grid can be downloaded locally as a sharp PNG, JPG or one-page PDF.
Is my Sudoku puzzle uploaded anywhere?
No. The puzzle is solved locally in your browser and is not transmitted to a server.