Hi folks,

Before I begin, I'm not plugging commercial software nor do I have my site set up with ads for revenue. This is just to get the word out there about a convenient, no-download solver that also works offline, and to potentially solicit code contributions from the open-source community.

So my solver is 100% javascript, with the CSS+HTML+Javascript inside a single HTML file so that you can save it and use the solver offline. Being 100% Javascript, it's also open-source and licensed under the GPL.

There's also a quantitative instance "hardness" ranker, which is based on the following logic:

1. If an instance is solvable purely with logic, it's difficulty is 0.

2. For the portion of the board that CANNOT be solved by logic, the difficulty is the log of the expected search tree size.

This gives an exponential scale for ranking Sudoku instances from the perspective of computer solvability.

I'd like to encourage you all to check it out, distribute the code (under GPL terms of course) and as always, I am more than open to suggested enhancements or code contributions.

http://compbio.cs.uic.edu/~mayank/fapanosss.html

Thanks,

-Mayank