While it’s not shattering to your search engine optimisation to not “nofollow” any external hyperlinks, you are passing on benefits to external websites and blogs you have no relation with and unless you have a backlink on their website or blog back to yours, you are not getting any stringent benefits back in return. Because WordPress doesn’t have any built-in features to “nofollow” any hyperlinks you add to your blog posts (and even so, it’s still slower than having an automated solution), there is an easy and convenient solution by using a plugin called External Nofollow that does what you’d want – makes any external backlinks have a rel attribute with nofollow value. Although the two plugins we tested that do this do not work if you have your blog on a subdomain, as, predictably, they are only programmed to take into consideration the subdomain and so any URLs not within the subdomain will be considered external, so unless you have your blog on the main domain name, do not use the plugins as they will “nofollow” any URLs to areas on the main site of your domain name which can adversely affect your SEO.
Why should I use this plugin?
There’s no need to worry about nofollow’ing any external hyperlinks – the plugin does this for you. You simply add the hyperlink and once published, the hyperlink will be nofollow. I would recommend when using this plugin to test it by viewing your blog page source code to make sure the plugin works perfectly.
What does the “nofollow” alt attribute value do?
As it states, it tells search engines that comply with “nofollow” to not follow hyperlinks that have their rel attribute set to nofollow. Search engines such as Google and Bing comply with nofollow, as well as robots.txt exclusions.