Nick Momrik

Counts the total number of words in all posts or the number of words in a single post.
<h3>Configuration</h3>
The default is to count the total number of words in all posts. If you would like the number of words displayed for a particular post or page, use the following inside “the loop”
<pre><code><?php mdv_post_word_count(true); ?>
</code></pre>

Post Word Count

Counts the total number of words in all posts or the number of words in a single post.

jojaba

This plugin replaces the word count info in bottom of the edit post window by the characters/words count (on the fly). Additionnaly, you can limit the characters/words count for defined user roles.
Here’s the list of the settings (see screenshots for further infos):
<ul>
<li>Enable or disable characters/words count limit.</li>
<li>Max characters and words count setting</li>
<li>Warning characters and words count setting (the count before max count when the warning is fired)</li>
<li>Output Format. You can define how you would like to see the output displayed using different placeholders : <code>#chars</code> (the character count that has been typed), <code>#words</code> (The number of words), <code>#maxChars</code> (the max characters allowed), <code>#leftChars</code> (the characters count left),<code>#maxWords</code> (the max words allowed), <code>#leftWords</code> (the words count left).</li>
<li>Choose what user role should be limited. Default set to contributor role.</li>
<li>Choose the post types that should be limited. Default set to post.</li>
<li>Set customised messages for warning or for contributor submission.</li>
</ul>
Availabe languages : english and french.

WordPress Word Count and Limit

Counts dynamically the characters/words in edit post window and limit the characters/words count if needed for one or more user roles.

Post Word Count vs WordPress Word Count and Limit