What is Sudoku?
Sudoku is a popular logic-based number puzzle game played on a 9x9 grid. The objective is to fill each cell with numbers from 1 to 9, following three simple rules:
- Each row must contain all digits from 1 to 9 without repetition
- Each column must contain all digits from 1 to 9 without repetition
- Each of the nine 3x3 boxes must contain all digits from 1 to 9 without repetition
Sudoku puzzles come in various difficulty levels, from easy puzzles suitable for beginners to expert-level challenges that require advanced solving techniques.
How to Use This Sudoku Solver
Solve Your Own Puzzle
Enter your Sudoku puzzle into the grid by clicking on cells and typing numbers 1-9. Once you've entered all the given numbers, click the Solve button to get an instant solution using our advanced backtracking algorithm.
Human Solve Method
Click Human Solve to see a step-by-step solution using human solving techniques such as Naked Singles, Hidden Singles, Pointing Pairs, X-Wing, and Y-Wing patterns. This feature is perfect for learning how to solve Sudoku puzzles yourself.
Generate New Puzzles
Use the difficulty buttons on the left to generate fresh Sudoku puzzles:
- Easy: Perfect for beginners (40-45 clues)
- Medium: Moderate challenge (35-40 clues)
- Hard: Requires advanced techniques (30-35 clues)
- Expert: Very challenging (27-30 clues)
- Evil: Extremely difficult (24-27 clues)
Pencil Marks & Candidates
Enable Pencil Mode to add candidate numbers (possible values) to cells. Use Show Candidates to display or hide these marks. The Auto-update candidates option automatically calculates possible values for empty cells.
Share Puzzles
Click Share Puzzle to copy a link to your current puzzle. Send the link to friends or save it for later - the puzzle will load automatically when the link is opened.