Extra Regions

Killer Sudoku

Cages must sum to the given total — no digit repeats within a cage

Ready to Play!

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

How Killer Sudoku Works

Dashed cages carve up the grid, each labelled with the total its cells must reach, and no value repeats inside a cage. There are usually no given digits at all — totals, cage shapes, and the 45-per-unit identity drive every deduction. The benchmark arithmetic variant: tough, fair, and addictive.

For the complete rules, worked examples and solving techniques, read the full How to Play Killer Sudoku guide.

Standard Sudoku Rules Still Apply

Like all Sudoku variants, Killer 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