Jacob N. Breetvelt

This plugin can display a sudoku puzzle diagram on your website. 
It comes with 200.000 unique puzzles in 7 different levels of difficulty. 
The number of times a puzzle is successfully solved or failed is registered. 
There is simple help and statistics available at the front-end.

WP Sudoku Plus

This plugin displays a sudoku puzzle diagram on your website that the visitor can try to solve.

tibouille

This plugin allows you to include sudoku puzzles in your blogs with a simple shortcode. The sudoku puzzles can be inserted everywhere: in your theme files, posts and pages.
Parameters:
<ul>
<li>Size of the sudoku puzzle: 9×9, 10×10, 12×12, 16×16.</li>
<li>Difficulty level: easy, medium, hard, expert.</li>
<li>Width (and height) in pixels (not less than 450 px).</li>
<li>Background color.</li>
<li>Available in english and french.</li>
</ul>
For more details and examples visit the plugin page on <a href="http://www.live-sudoku.com/site-perso/wordpress" rel="nofollow ugc">live sudoku</a> or on <a href="http://www.le-sudoku.fr/site-perso/wordpress" rel="nofollow ugc">Le sudoku</a> if you speak french.
<h3>How to use</h3>
Visit <a href="http://www.live-sudoku.com/site-perso/wordpress" rel="nofollow ugc">sudoku in your WordPress blog</a> or if you speak french <a href="http://www.le-sudoku.fr/site-perso/wordpress" rel="nofollow ugc">sudoku sur votre blog WordPress</a>. 
You can also check out the source repositories on <a href="https://bitbucket.org/lesudoku/sudoku" rel="nofollow ugc">bitbucket</a> or <a href="https://github.com/sudoku/sudoku" rel="nofollow ugc">github</a>.

Sudoku Shortcode

Fast and easy integration of sudoku puzzles into your blogs, with some parameters.

WP Sudoku Plus vs Sudoku Shortcode