Last updated on July 17, 2020
Noreferrer Noopener Noindex Nofollow meta tags are robot meta tags, which are pieces of code that provide crawlers instructions on how to crawl or index web page content, example a page or a link.
It is a strong recommendation, but Google does not necessary follow it explicitly. Nonetheless, it’s still a best practise for healthy SEO.
Noreferrer Noopener meta tags
If your website is on WordPress, you need to know that whenever you create a link (regardless internal or external link) in a post/page that opens in new window, WordPress auto append rel=”noreferrer noopener” to the link.
Whereas target=”_blank” refers to the instruction to open in new window.
WordPress implemented this after a community discussion and serious deliberation to solve risk of phishing arising from opening a link in another window.
It is good, and has no issue with SEO.
So what does Noreferrer and Noopener do?
A rel="noreferrer"tag indicates no referrer information to be leaked on following the link. It mainly specifies browser not to pass an HTTP referrer header if the person clicks on the link.
Does rel=”noreferrer” affects my affiliate links and the ability to detect if affiliate should get paid for referral?
No, simply because most affiliates are tracked by affiliate ID or referral code, and it’s different methodology.
A rel="noopener" tag is also implemented to avoid risk of malicious websites trying to exploit from opening a link in new window.
There are some JavaScript features that allow a new tab to get control of its referring window. For example if you link to an external website that is affected by the malicious code, then the affected website can change the referring page (your website) to steal information and spread malicious code (without you or the other party even knowing!)
Adding this rel="noopener" tag prevents that.
Noindex Nofollow meta tags
A noindex tag prevents a page, for example, from being indexed and displayed in search engine result pages.
Why would you want to do that? There are some contents that is private, or not useful to be found on Search . For example, your webmaster admin login page. It will be weird to be found on Google Search, isn’t it?
Also, you can use noindex tag to tell Google not to index certain pages that you want to deprecate. These type of pages could be irrelevant or expired, and you only want to keep them live, but not searchable.
A nofollow attribute prevents your website from passing on SEO link juice to the linked external website. It is also used if you do not trust nor endorse the page you are linking to, but only referring readers to it for info.
However, it’s NOT a best practise to include it in all your external links. Google might see your site as gaming the search engine. It is healthy to have a balance of dofollow links to authoritative sites.
Confused? Too technical?
That’s why I am always a fan of WordPress and its plugins.. simply because it’s open sourced and supported by community.
Rank Math plugin helps you sort all these needs with just clicks and human language.
For each of your page or post, you can choose whether to Index or Noindex. To tell the search engine to follow each links in it, or not to follow, and much more.
You can also set the rule on higher level of your url hierarchy. For example, it’s recommended to noindex your categories or tags unless if you have unique and useful contents on www.yourwebsite.com/categoryA (as illustration).
Most of the time these pages (categories and tags) do not have useful contents but rather duplicate (snippets) of your post contents.
Last but not least, if you are a Yoast plugin user, you need to choose between one because both plugins are of competing features.