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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' Andrew Stuart 1 Andrew Stuart 2 Andrew Stuart 3 Andrew Stuart 4 Andrew Stuart 5 Andrew Stuart 6 Andrew Stuart 7 Andrew Stuart 8 Moonlotus Onion Double Mirror Cyndie Tornado Cross Worm Cabbage Stripes H Wednesday ZigZag Legoman Offside Anonymous 1 Tim Tang Andrew Stuart New 24 Andrew Stuart New 25 Andrew Stuart New 26 Andrew Stuart New 27 Andrew Stuart New 28 Custom Step 2: Pick an example here Example 1 Example 2 Example 3 Example 4

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 are important new ones such as the Law of Leftovers.

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

 Show bi-values cells Show Strong (bi-location) links in Boxes Rows Columns 1 2 3 4 5 6 7 8 9

Errors? [CRTL]+[F5] to clear and download the latest script files
 A B C D E F G H J
Version 2.26
See the Strategy Home Page for strategy guides

Coordinate system: Letter/Number rYcX

 1 2 3 4 5 6 7 8 9
 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 Reduction 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. Inference 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's Bingo

Box numbers referred to in results:

## 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 By Andrew Stuart and Rui GonÃ§alves, Syndicated Puzzles
 Email your puzzle to a friend 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 22-Jul-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