Free Killer Sudoku Solver

Killer Sudoku Solver: Solve Cage Sum Puzzles Online

Our free Killer Sudoku Solver is built for puzzles where ordinary Sudoku logic meets arithmetic. Instead of only entering a grid of given digits, you can draw cage shapes, assign each cage a sum, add any printed givens, and let the solver test the full set of Killer Sudoku rules.

The tool checks standard 9x9 Sudoku constraints first: every row, column, and 3x3 box must contain the digits 1 to 9 without repeats. It then applies Killer Sudoku cage rules. Each cage must add up to its target total, and no digit may repeat inside the same cage. This makes the solver useful for classic Killer Sudoku, hybrid puzzles that include a few givens, and handmade grids you want to verify.

How to Use the Killer Sudoku Solver

1. Choose Cages mode and drag across touching cells to create a cage shape.
2. Enter the cage total and save it. Click an existing cage to edit or delete it.
3. Switch to Numbers mode if the puzzle has printed givens, then click cells and enter digits.
4. Press Solve to find a completed grid. The solver also reports whether the setup has a unique solution.

Why Cage Entry Works Better Than a Text Box

Killer Sudoku puzzles are visual. A long text format is fast for machines but slow for humans, especially when cages bend around boxes. The drag-to-select cage editor lets you copy a puzzle from a book or website in the same way you see it: shape first, total second. The cage list below the grid keeps every total visible so mistakes are easier to spot before solving.

What the Solver Checks

• Duplicate digits in rows, columns, boxes, and cages.
• Cages whose current digits already exceed their target sum.
• Completed cages that do not add up to the target.
• Whether the puzzle has one solution or multiple possible solutions.

Everything runs locally in your browser. Your Killer Sudoku grid, cage layout, and exported JSON are not uploaded to a server.