Latest Changes and Additions

A quick list of the latest updates and additions to this site:

Strategy Families
Date Created: Saturday 12-Apr-2008
Last Updated: Monday 30-Jun-2025
This is the index to the all the fully documented strategies used to solve Sudoku, Jigsaw Sudoku, Sudoku X and Killer Sudoku.

Sudoku Solver - Version History
Date Created: Sunday 13-Apr-2008
Last Updated: Friday 20-Jun-2025


Chute Remote Pairs
Date Created: Friday 24-Jan-2025
Last Updated: Monday 16-Jun-2025
A simple pattern to try early on

Y-Wing Strategy
Date Created: Friday 11-Apr-2008
Last Updated: Monday 16-Jun-2025
Sudoku Strategy. Y-Wings are simple three cell formations used to eliminate a candidate in a fourth cell. They are also the shortest versions of certain types of Alternating Inference Chains.

Cage Comparison
Date Created: Sunday 7-Aug-2011
Last Updated: Friday 13-Jun-2025


Sudoku Player
Date Created: Friday 13-Jan-2023
Last Updated: Thursday 12-Jun-2025


Daily Sudoku
Date Created: Saturday 12-Apr-2008
Last Updated: Sunday 8-Jun-2025
The Daily Sudoku puzzle by Andrew Stuart. This Sudoku can be completed directly on the web page - just enter numbers in the cells. Have fun!

X-Cycles
Date Created: Saturday 12-Apr-2008
Last Updated: Monday 26-May-2025
Sudoku Strategy. X-Cycles are simple chaining strategies that stick to candidate N. They are Alternating Inference Chains based on following the consequences of turning candidates on and off.

Guardians
Date Created: Friday 11-Apr-2008
Last Updated: Sunday 25-May-2025
Sudoku Strategy (depreciated). Guardians is a complicated way of looking at what is ultimately a nice loop with off-chain eliminations.

Unit Forcing Chains
Date Created: Saturday 6-Mar-2010
Last Updated: Sunday 25-May-2025
Sudoku Strategy. This is a Forcing Chains Strategy. It finds eliminations by comparing the results of chains starting with all candidates N in a unit and assuming any of them are turned on.