How to Check if a Sudoku Is Valid
Check whether a Sudoku board is valid by reviewing rows, columns, boxes, clue conflicts, and solution uniqueness.
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The practical answer
Validity has two layers: no current rule conflicts and exactly one final solution.
- Check duplicate digits first.
- Then confirm the puzzle has a solution.
- Finally verify uniqueness if you are making or publishing a puzzle.
Where to go next
If you are ready to act on this, use the main Pure Sudoku page built for this intent: How to Check if a Sudoku Is Valid.
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