Free to use, no account
Sudoku Solver
Paste or type a classic 9×9 Sudoku grid. The solver checks conflicting clues, searches for up to two solutions, and tells you whether uniqueness was proven. Your puzzle stays in this browser.
The solver works in your browser. It checks at most 200,000 search steps and reports when that limit prevents a conclusion.
Solution grid
How do I use this Sudoku solver?
Enter exactly 81 cells in row order. Use digits 1–9 for clues and 0 or a period for an empty cell. Spaces and line breaks are allowed. Solve to see one solution and whether the search proved it is unique.
Frequently asked questions
How do I use this Sudoku solver?
Enter exactly 81 cells in row order. Use digits 1–9 for clues and 0 or a period for an empty cell. Spaces and line breaks are allowed. Solve to see one solution and whether the search proved it is unique.
Is my Sudoku puzzle uploaded?
No. Parsing and solving run in this browser. The grid is not uploaded or saved by this tool.
How should I format the Sudoku puzzle?
Enter nine rows of nine cells, or paste 81 characters in row order. Use 1–9 for clues and 0 or a period for blanks. Spaces and line breaks are ignored.
Does the solver prove that a puzzle has one solution?
It searches for up to two solutions. It reports unique only when the search finishes and finds exactly one; if it finds two, the puzzle has multiple solutions. A safety limit can make a difficult puzzle inconclusive.
Does it read a Sudoku photo or show human solving steps?
No. Enter the digits yourself; this tool does not use a camera or OCR, and it does not claim to explain human solving techniques.