In the default setup, WordPress does not generate meta descriptions. In some WordPress templates, however, designers trigger WordPress to generate meta descriptions from either the Page/Post excerpt (but you'll have to remember to create excerpts for all Posts and Pages) or from the body text of the Post or Page. Obviously, having no meta description tags for Pages and Posts is not ideal in a search environment, and generating the tags from body text isn't much better.

So, we again recommend the must-have plugin, WordPress SEO by Yoast. The following screenshot shows the WordPress SEO plugin in use on a Post edit page. This plugin adds two handy features: an automatic character counter is displayed just under the Meta description edit field, and a Snippet Preview that lets you craft meta descriptions of precise length: