gerrygooner

This WordPress plugin will cleanup your WordPress database, performing the following actions:
<ul>
<li>Remove all post revisions.</li>
<li>Remove all spam comments.</li>
<li>Remove all unapproved comments.</li>
<li>Remove all unused tags.</li>
<li>Remove all unused post meta.</li>
<li>Optimize MySQL tables by removing all unused table space.</li>
</ul>
Based on WP-Cleanup by JortK, this plugin replaces usage of mysql_query() that was deprecated in PHP 5.5 with WP_Query functions .

WP-CleanDB

Dead Writers Society

Light and fast wp_head() cleaner. Just activate it and all unnecessary code will be deleted from site header section. It will improve loading speed of your website.
This plugin will remove:
<ul>
<li>WordPress version</li>
<li>shortlink</li>
<li>Really Simple Discovery link</li>
<li>RSS feed links</li>
<li>all extra RSS feed links</li>
<li>wlwmanifest.xml</li>
<li>meta rel=dns-prefetch href=//s.w.org</li>
<li>the next and previous post links</li>
<li>Emoji icons</li>
<li>WordPress REST API</li>
<li>oEmbed</li>
</ul>
Feeds (RSS, RSS2, Atom & RDF) and comments feeds will be disabled and redirected to home page for security reasons.

Nietzsche – WP Head Cleaner

This plugin cleans up the wp_head() and removes unnecessary code.

WP-CleanDB vs Nietzsche – WP Head Cleaner