WordPress allows you to open a link in a new window by default but it doesn’t allow you to easily add rel=”nofollow”. You either have to nofollow tag each links automatically, or manually add nofolow tag to each link by editing the HTML code. These two are either tedious or too much work.
Each time you link your own site or an external site, you are transferring SEO points to that page. These SEO points, also known as, Link juice are what makes your page, or the page you are linking to higher than the rest of the page who aren’t linked.
In this post, we’ll show you an easy way to add rel=nofollow tag to a link in the comments section of your page.
Read the rest of the post here: http://www.wpbeginner.com/plugins/how-to-add-a-nofollow-checkbox-to-insert-link-section-in-wordpress/