Non-Consecutive Sudoku
No two orthogonally adjacent cells may contain consecutive digits
Non-Consecutive Sudoku is fully playable. Choose a difficulty and start solving.
Non-Consecutive Sudoku imposes a global constraint: no two cells that share an edge (orthogonally adjacent) can contain consecutive digits. So if a cell contains 5, all its neighbours must avoid 4 and 6. This single rule dramatically limits candidate placements and can reduce a standard givens count while still producing a uniquely solvable puzzle.
Like all Sudoku variants, Non-Consecutive Sudoku builds on the classic 9×9 foundation. Every row, column, and 3×3 box must contain each digit from 1 to 9 exactly once. The variant constraint is added on top of these standard rules, never replacing them.
If you're new to Sudoku, start by learning the basic rules and techniques before attempting variants.
Techniques Useful for This Variant
| Technique | How it applies |
|---|---|
| Pencil Marks / Notes | Essential for tracking candidates alongside the variant constraint |
| Obvious Singles | Cells narrowed to one candidate by the combined constraints |
| Hidden Singles | Digits with only one valid cell in a unit after variant elimination |
| Pairs and Triples | Locked candidates exposed by the additional constraint |