svil4ok

Get tags on every single post (is_single()) and put them in meta keywords tag in header (wp_head()). Otherwise it’ll use the keywords define in $default_keywords. Get the_excerpt() and put it in meta description tag in header (wp_head()). Otherwise it’ll use the description define in $default_description.
Requires the wp_head() tag !

Meta Keywords & Description

mukeshjakhar888

The first complete free all in one SEO solution for WordPress websites, including home page, archive pages, single post page etc. you can also set custom keywords, social media links for your hole website. This plugin helps you in SEO by adding Meta keywords, Description, facebook twitter google plus meta tags to each and every page, post, archive. (category, tag, date, day and year). This plugin also allows you to specify common keywords to be included on every web page. Plugin from one of the best coder <a href="http://www.phpkida.com/mukesh-jakhar-wordpress-php-web-developer-and-designer/" rel="nofollow ugc">Mukesh Jakhar</a>. For any support just leave your question at our <a href="http://www.phpkida.com/swt-seo-helper/" rel="nofollow ugc">SWT SEO HELPER PLUGIN</a> page. 
Uses Title, Description, Categories, tags, Compulsory keywords (provided by you in setting) for keywords generation.

SWT SEO Helper

This is awesome free seo plugin, guys should be use once, very simple optimize on single setting page this is working great...

This is awesome free seo plugin, guys should be use once

SWT SEO Helper auto generating keywords, Adds Meta keywords and Description, facebook twitter google plus meta tags to each and every page, post, arch …

Meta Keywords & Description vs SWT SEO Helper