Play Killer Sudoku Online

Killer Sudoku is a Sudoku variant that combines classic grid logic with simple cage sums. Fill rows, columns, and boxes as usual. Each dotted cage must add up to its small number, and numbers cannot repeat inside the same cage.

How Killer Sudoku is different

Classic Sudoku gives fixed numbers in the grid. Killer Sudoku replaces many of those clues with small sum numbers in dotted cages, so each move can use both placement logic and gentle arithmetic.

Choose a Killer Sudoku difficulty

Start with Easy Killer to learn cage sums, then move to Medium, Hard, or Expert as the combinations become less obvious. The classic Sudoku rules still apply — the cages simply add an extra layer.

Quick tips

• Look for small cages with two or three cells first — they have the fewest possible combinations
• Remember that numbers cannot repeat inside a cage, which often eliminates the obvious pair
• Use normal Sudoku row, column, and box logic alongside the sums
• A cage of size 1 always contains its sum as a single digit