Irregular Diagonal Sudoku
Combines jigsaw regions with main diagonal constraints
Irregular Diagonal Sudoku is fully playable. Choose a difficulty and start solving.
Irregular Diagonal Sudoku combines two variant types: the irregular jigsaw regions of Jigsaw Sudoku and the diagonal constraints of Diagonal Sudoku. Both main diagonals and all irregular regions must contain 1–9. The combination creates highly constrained puzzles with unique solving logic.
Like all Sudoku variants, Irregular Diagonal 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 |