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Jigsaw Sudoku Solver
Solve Path now excludes unchecked strategies
Candidates can be Edited or Highlighted Chained Coloured,  Shown
Enter clues or solutions
1 2 3 4 5 6 7 8 9
Auto Tab Auto Clear
Clues+Solved: 0/81
Step 1: Choose the 'shape'
Step 2: Pick an example here


New: Custom jigsaw shapes can now be set up. Read the help page
Quick help: The differences

Jigsaw Sudokus are the same as normal sudoku except for the shapes of the boxes. Some strategies cannot be used (see below) but there is one important addition: The Law of Leftovers.

In order to use this solver you need to pick the correct grid shape from the list above. Only then type the numbers into the small grid, use the Import button or pick an example from the example list.

There are 20 Jigsaw shapes as used on www.sudoku.org.uk and four interesting examples for each shape, 80 examples in total.

For all other help guides for the solver, see the Sudoku Solver.

Please report any bugs - Thanks.

If you are getting errors please
clear your browser cache
to retrieve the latest script files.
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Version 2.20
See the Strategy Home Page for strategy guides.
Coordinate system: Letter/Number rYcX

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Check for Solved Cells   
Show Possibles  
1: Hidden Singles  
2: Naked Pairs/Triples  
3: Hidden Pairs/Triples 
4: Naked Quads 
5: Pointing Pairs  
6: Box/Line Reduction  
Tough Strategies
7: Double Pointing Pairs  
8: Double Line/Box Reduct.  
9: Law of Leftovers  
10: X-Wing  
11: Simple Colouring  
12: Y-Wing  
13: Rectangle Elimination  
14: Swordfish  
15: XYZ Wing  
Diabolical Strategies
16: X-Cycles  
17: XY-Chain  
18: 3D Medusa  
19: Jellyfish  
20: WXYZ Wing  
Extreme Strategies
21: Grouped X-Cycles  
22: Altern. Infern. Chains 
23: Digit Forcing Chains  
24: Nishio Forcing Chains 
25: Cell Forcing Chains  
26: Unit Forcing Chains  
27: Almost Locked Sets  
28: Death Blossom  
29: Pattern Overlay Method  
30: Quad Forcing Chains  
"Trial and Error" 
31: Bowman Bingo 

Box numbers refered to in
strategy results:


Want to know what shape is what?
View the Jigsaw Shape List

Welcome to my Jigsaw Sudoku page

In many ways Jigsaw's are even more interesting than normal Sudokus, although they have not been studied as much.

All bar a few of the classic Sudoku strategies pertain to Jigsaws, but in the current version I have removed Uniqueness tests since it is very difficult to determine valid 'Deadly Rectangle' in the jumble of shapes. However the non square shapes open up the opportunity to use some neat strategies only found in Jigsaws such as the Law of Leftovers, Double Pointing Pairs and Double Line/Box Reduction. Also puzzles are often defeated using simple Pointing Pairs and Box/Line Removal as the shapes of the boxes lead to more opportunities for these strategies.

I have now added a page showing all the Jigsaw Shapes

All feedback, comments, arguments, bug reports and strategy ideas are welcome. There is a FEEDBACK form with a column displaying comments and questions. Many thanks to all the people who have done so and helped improve this solver.


New in version 2.20 (19th June 2024)
Custom Jigsaw Shapes! Choose [Enter New Jigsaw] and set up a Jigsaw you found in the wild.

New in version 2.14 - 2.16 (May 2024)
New and much faster Solution Count.
New Solution Count and Email popups.
Packed strings for transporting candidates allowed on url and import
Added candidate chaining and colouring.


Added some new 'shape' patterns - see the end of the example pull down list. These are used in the new Jigsaw Sudoku Puzzle Packs. The examples here are gentle, moderate, tough and extreme - four each for each new shape pattern.

Version history here

New in version 1.38 (November 21st 2006)
Release of the Jigsaw Solver

All Solutions to a Jigsaw Sudoku
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By Andrew Stuart and Rui Gonçalves, Syndicated Puzzles
Email your puzzle to a friend
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Copy and paste the contents of the green box into your email program and send it off.
The links contain the puzzle which will load when your friend visits the Sudoku Solver.
 
 

Custom Jigsaw Sudoku

You can create a custom shape and it will be stored as a cookie.

Choose colours in the top row and click on cells on the board.

Your Jigsaw is ready when all colours have nine cells

Start with an existing pattern:


and clear board of clues


To use more than one custom shape load them from the parameter line. Look at the format in [Email This Board] and substitute your 81 character custom map for the shape number.

Solver created on 31-Mar-2007.

This page was last modified on 18-Jun-2024
All code and design is copyright and for personal use only and may not be reproduced elsewhere.
Copyright Andrew Stuart @ Syndicated Puzzles, 2005-2023, Privacy