What is a Robots.txt File and Why do you Need One?

The robots.txt file is used to control which website pages can be accessed by specific search engine crawlers. But how does it work, and why do you need one? Here, we dive deeper into the technicalities of robots.txt and provide tips on how to use it to your advantage.  


How Does a Robots.txt File Work?

A robots.txt file contains directives (instructions) about which user agents can or cannot crawl your website. A user agent is the specific web crawler that you are providing the directives to. The instructions in the robots.txt will include certain commands that will either allow or disallow access to certain pages and folders of your website, or the entire site. Basically, the robots.txt file tells Google’s bots how to read your site when indexing it.

Using the correct syntax is crucial when creating a robots.txt file. Here are two examples of a basic robots.txt file, provided by Moz:

User-agent: * Disallow: /

Using this syntax will block website crawlers from accessing all your website pages, including the homepage.

User-agent: * Disallow:

Using this syntax will allow the user agent to access all pages of the website, including the homepage.

If you want to block access of an individual webpage, this must be specified in the syntax of the file – as you can see in the Moz example below:

User-agent: Bingbot Disallow: /example-subfolder/blocked-page.html

In addition to blocking user-agent access to certain areas of your website, you can also use a robots.txt file to create a crawl delay. A crawl delay specifies how long the user agent should wait before loading and crawling the page.


How to Create One

Creating a robots.txt file is straightforward, as it is actually just a basic text file. As explained by this article, it can be created using almost any text editor, such as Notepad or TextEdit.

The robots.txt file must be hosted in the root directory of the domain to be found (i.e. https://pureseo.com/robots.txt), as this is the first page that website crawlers open when they visit your site. Each website domain should only contain one robot.txt file, and it must be named ‘robots.txt.’  

Once you’ve named the file, the next step is to add rules about which parts of the website can or cannot be crawled by specified user-agents. The type of rules you enter into your robots.txt file will depend on the content of your website, and what you wish to accomplish. After you’ve established the rules for your robots.txt, you can upload the file. Make sure to test whether the file is publicly accessible, before storing it in the domain. You can do this with Google’s Robots.txt Tester.


Why Use a Robots.Txt File?

There are several benefits of using a robots.txt file for your website. While it is not essential for all websites to have one, it is still a powerful tool that can give you more control over how search engines crawl your pages and folders.

  • Maintain Privacy – One of the main reasons website creators use robots.txt is to keep bots away from private sections of their website. This is particularly useful when you’re in the process of creating a staging site, and you don’t want a specific page public yet.
  • Help Search Engines Find Your Site Map –Your sitemap allows crawlers to access the most important areas of your website more efficiently. The robots.txt file can help search engines locate your site map, which will have benefits for SEO.
  • Prevent the Appearance of Duplicate Content – Having duplicate content on your website could harm your SEO With a robot.txt file, you can prevent duplicate content from appearing on the SERPs.
  • Prevent Server Overload – If crawlers load too much content at once it’s easy for servers to get overloaded with requests. With a robot.txt file, you can specify a craw delay, which will prevent this issue from occurring.


How to Use a Robots.txt File for SEO

Search engine optimisation is a key component of a successful website. Using robots.txt the right way could be great for your website’s SEO strategies, and doing it the wrong way could bring a lot of unintentional harm. When creating your robots.txt or making changes to it, it’s really important that you keep SEO best practice in mind and avoid common mistakes. Making a simple error in your robots.txt file could cause your entire website to be blocked by search engines.

For example, if there are any pages on your website that you want to be crawled by search engines, you must ensure that these aren’t accidently being completely blocked by robots.txt.

As Moz explains, the links featured on a blocked page will not be followed, which means the linked resources will not be crawled or indexed. This will negatively affect your link equity, which has a direct impact on your website’s SEO.  

Keep in mind that having too many ‘disallow’ instructions could harm website’s search rankings. Do not overdo this command, and only use it where it is necessary. Finally, always remember to check for syntax errors in your robots.txt before saving the file in the directory.


Have Questions about SEO?

Whether you’re creating your very first website or want to improve your existing SEO strategy, Pure SEO are here to help. As experts in SEO, we have the experience and expertise to help you with your digital-marketing strategies and web-related issues. Contact our team today and we will help set you up for success.


Robyn has lived in New Zealand for 15 years, after living in Trinidad for most of her childhood. Since arriving in New Zealand, she has travelled most of the country, and has also travelled abroad to North America, Asia and Europe. In her free time, Robyn loves going to the beach, discovering new places to eat, and spending time with family.

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