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 Killer Sudoku Solver Please report any bugs. Tested in IE and Firefox. Feedback: Form and User Comments/Questions Here
 Click to edit candidates or enter a solution: Show Candidates

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Clues+Solved: 0/81
 Pick an example here Gentle Example Moderate Example Tough Example Diabolical Example Extreme Example

Quick help: Using this Solver

You can pick examples from the list above. Click on Take Step to step through the solution. Unknown squares are filled with 'candidates' - possible solutions.
Any cells that are reduced to one possible candidate are solved.

You can enter a new Killer puzzle using the new 'designer' - click on "Enter new Killer". Once you fill in the clues and set up the cages correctly it can be solved.

Unlike the other solvers you can only edit the main board when solving. The small board only displays the clues.
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Version 2.06
See Strategy Overview documentation

Coordinate system: Letter/Number rYcX

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 Check for Solved Squares Show Possibles 1: Hidden Singles 3: Naked Pairs/Triples 4: Hidden Pairs/Triples 5: Quads 6: Killer Combinations (easy) 7: Innies and Outies (1 cell) 8: Pointing Pairs 9: Box/Line Reduction Tough Strategies 10: Cage Splitting 11: X-Wing 12: Simple Colouring 13: Y-Wing 14: Innies/Outies (2+ cells) 15: Killer Combo's (hard) 16: Cage/Unit Overlap 17: Cage Compare 18: Swordfish 19: XYZ Wing Diabolical Strategies 20: X-Cycles 21: XY-Chain 22: 3D Medusa 23: Jellyfish 24: WXYZ Wing 25: Aligned Pair Exclusion Extreme Strategies 26: Grouped X-Cycles 27: Finned X-Wing 28: Finned Swordfish 29: Altern. Inference Chains 30: Sue-de-Coq 31: Digit Forcing Chains 32: Nishio Forcing Chains 33: Cell Forcing Chains 34: Unit Forcing Chains 35: Almost Locked Sets 36: Death Blossom 37: Pattern Overlay Method 38: Quad Forcing Chains "Trial and Error" 39: Bowman Bingo

Please report any bugs - Thanks.

If you are getting errors please
to retrieve the latest script files

## Welcome to this new Killer Solver

I have been solving and making Killer Sudoku puzzles since 2005 and although my Sudoku solver has been part of this site since those early days I have not attempted a public solver until now. The main reason I have shied away from attempting it was the complexity of the puzzle in terms of the user interface. However, I hope I have now come up with a satisfactory solution. The independent 'Designer' handles the entering of the clues and cages. Keeping this separate and being able to (loosely) validate the entry should allow puzzle solvers a fairly quick way of setting up the puzzle for solving. I hope you agree and I'd love to hear your feedback.

You should also be aware of the Killer Cage Convention.

New in version 2.06 (September 8th 2017)
For Naked Pairs in a cage I've added the case where the two cells are diagonally positioned.

New in version 2.03 (August 29th 2015)
Killer Cage Convention will now clear off candidates in 'dog-leg' cages early in the list of checks - as and when solution numbers are found.

New in version 1.99 (April 9th 2014)
Unchecked strategies are now saved in a cookie.

New in version 1.94 (May 25th 2013)
Fixed some bugs and improved the text returned from cage combinations. Made sure the 'last remaining cell' in a cage was correctly being identified and now shows on the Hidden Singles stage.

New in version 1.91 (October 16th 2012)
Re-wrote the Innies/Outies algorithm to look for innies with more than one cell covering several sticking-out cages. Re-ordered the strategies to balance them against new calibrations.
Added Cage Comparison to the killer strategies.

New: Version 1.02 (June 13th 2009)
Killer Sudoku Solver released

Still to do:
1. Some kind of emailing and importing using only a single string. Unfortunately the information required to transport a Killer using a web address is a little too large. The puzzle requires the clues, the cages and the state of the board during play. So I haven't thought of an easy method to provide those features.
Solver created on 30-May-2009.