Steve Grunwell

<a href="https://codex.wordpress.org/Excerpt" rel="nofollow ugc">WordPress post excerpts</a> can be a great way to hand-craft the summary of your content. Unfortunately, writing post excerpts isn’t as nice of an experience as what you find elsewhere in WordPress. Want to include links in your excerpts, or bold some text? Hopefully you know some HTML!
Advanced Post Excerpts is designed to change that, by giving your editors an easy, intuitive interface for writing great post excerpts.
For complete details and/or to contribute to ongoing development, please <a href="https://github.com/stevegrunwell/advanced-post-excerpt" rel="nofollow ugc">visit this project on GitHub</a>.

Advanced Post Excerpt

Replace the default Post Excerpt meta box with a superior editing experience.

Seans0n

Custom Excerpts allows you to implement custom excerpt text, length, and to choose HTML tags to allow and whether to make the link nofollow or dofollow. Previously the only way to achieve this was to edit the WordPress core file formatting.php which meant changes would be lost after each update.
Related Links:
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<li><a href="http://www.seanbluestone.com/customizing-the_excerpt" rel="nofollow ugc">Plugin Homepage</a></li>
</ul>

Custom Excerpts

Custom Excerpts allows you to create a custom excerpt length, choose HTML tags to allow and whether to make the link nofollow or dofollow.

Advanced Post Excerpt vs Custom Excerpts