I know you guys out there are trying to make your blog Nofollow because this can save the PR juice and increase your blog PR (PageRank) effectively. The Nofollow tag is basically used to let search engines know that not to follow the URLs that has Nofollow attribute. See how Nofollow attribute looks like:
<a rel="nofollow" href="http://softstribe.com/">Web Development Resources</a>
So, as we have already written several articles about How to increase external links for your blog, How to mask external links to internal links in WordPress, and now going to add NoFollow automatically over all external links in WordPress.
Handle External Links
Handle External Links helps you to control when to set rel=”nofollow” on external links and when not only in WordPress. You can set the nofollow attribute depending on the 404 status, PageRank, whether the URL is blacklisted or white-listed, and much more flexible.
How it Works?
All you have to do is to install Handle External Links in your blog, afterwards go to Settings > Handle External Links and configure the settings as you want them.