Renban Sudoku
Purple lines must contain consecutive digits in any order
Renban Sudoku is fully playable. Choose a difficulty and start solving.
Renban Sudoku draws purple lines on the grid. The digits on any purple line must form a set of consecutive integers (like 3,4,5 or 7,8), though they can appear in any order along the line. The length of the line tells you exactly how many consecutive numbers are involved. This creates powerful range restrictions: a 5-cell Renban line can only span 5 consecutive values from the possible range 1–9.
Like all Sudoku variants, Renban 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 |