Clone Sudoku
Marked regions must contain identical digit arrangements
Clone Sudoku is fully playable. Choose a difficulty and start solving.
Two identically shaped zones must end up with identical contents, cell for cell. Anything you learn in one zone teleports to the other, halving the real work — and doubling the consequences of an error. A satisfying mirror-logic twist at moderate difficulty.
For the complete rules, worked examples and solving techniques, read the full How to Play Clone Sudoku guide.
Like all Sudoku variants, Clone 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 |