Cell Relationships

Consecutive Sudoku

Bars between cells mean those two digits are consecutive

Ready to Play!

Consecutive Sudoku is fully playable. Choose a difficulty and start solving.

How Consecutive Sudoku Works

Consecutive Sudoku marks bars between pairs of adjacent cells. A bar means the two digits in those cells differ by exactly 1 — they are consecutive. When used with the negative constraint (no bar = not consecutive), this gives information about every adjacent pair in the entire grid, creating a powerful constraint network.

Standard Sudoku Rules Still Apply

Like all Sudoku variants, 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

TechniqueHow it applies
Pencil Marks / NotesEssential for tracking candidates alongside the variant constraint
Obvious SinglesCells narrowed to one candidate by the combined constraints
Hidden SinglesDigits with only one valid cell in a unit after variant elimination
Pairs and TriplesLocked candidates exposed by the additional constraint