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What is a 404 Error?

Everyone has seen at least one version of a 404 error at some point in their internet browsing experiences. Learn more about what is a 404 error in today's blog.

14 Dec, 21 by Antoniy Yushkevych 11 min Read

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The HTTP 404, 404 Not Found, 404, 404 Error, Page Not Found, or File Not Found error message is related to a Hypertext Transfer Protocol (HTTP). It is a standard response provided by the system. This is indicative that the said computer network communications failed. In a nutshell, the browser used by the user was unable to locate the requested file. This indicates that the designated browser somehow communicated with the requested server, but the provided server could not supply the requested file. It can be mainly missing; thus, they were not able to communicate. It can even be seen when the requested server doesn’t want to reveal the requested information due to privacy and security concerns. 

The website server will typically show these messages regarding broken links or dead links owing to this modality; it is one of the most common errors encountered by the users. 

A web browser requests several response codes and an optional code at times; it may be necessary or unauthorized (by status code). These messages are necessary to answer a request when you communicate over HTTP. Code 404 essentially shows a client error; for example, there might be a broken Uniform Resource Locator (URL). In previous procedures such as FTP and NNTP, HTTP's usage of three-digit codes is comparable. A human-readable cause sentence follows a 404 response code at the HTTP level. The HTTP standard indicates the sentence "nonfounded” and a default number of web servers.

Dead links often remain as long as the operators don't know that the referenced information has been removed or relocated. Although they are no longer available online, many websites are still visible in the search engine results pages (SERPs) (or at least not at the specified URL). Other websites, such as blogs, news portals, etc., that have been deleted or may now be located under a new URL are frequently not notified.


A "not found" problem was noted on certain sites when a regular web page with a "200 OK" response code was returned, fraudulently reporting the correctly loaded page, called 404 software. In 2004 Ziv Bar-Yossef invented the phrase 'soft 404.' 

We observe two types of online replies 404 ('File not found): 'hard 404s' and 'soft 404s.' We oppose using so-called "soft 404s" since they might create a confused user and search engine experience. Websites that provide 'soft 404' send a 200 reply code instead of giving a 404 reply code to a non-existent URL. The 200 response contents are frequently the site's homepage or a mistake page. How's the user looking at a 404 soft? This is a funny mockup of a 404 soft: This website gives a 200 response code and the site's main page for non-existent URLs.

As seen in research, soft 404s confuse consumers, and search engines may invest a large part of their time in crawling and indexing unresisting; there might be frequently duplicate URLs on your site. This can negatively influence your website's coverage—due to Googlebot's time on missing pages, and it is not possible to find or visit your unusual URLs so fast as often. Instead of returning a soft 404, what should you do? Returning a 404 response code is significantly better and explains to users explicitly that the file was not found. Search engines and many people are glad about this.

For automated techniques to determine if a link is broken, Soft 404s are troublesome. Some search engines, such as Yahoo and Google, employ soft 404 automatic search methods. The use of soft 404s with some HTTP server software may arise from setup mistakes.

Many companies utilize 404 error pages to add comedy on a serious website otherwise. For instance, Metro UK depicts a polar bear on a board, and Left Logic provides basic sketching software for the Web Development Agency. The main political parties utilized their 404 pages during the 2015 United Kingdom general election campaign to aim at political opponents or to present potential supporter’s important policies. The NotFound project developed in Europe by many European organizations, including Missing Children Europe and Children Focus.


Servers with proxies

A 404 error is generated by certain proxy servers when a 500-range error code is more correct. If a remote host problem (for example, problems in the hostname resolution or refusals to TCP connections) the proxy server cannot fulfill a page request, this should be indicated as a 5xx internal server error, but can send a 404 error also. This can confuse applications with particular answers since they no longer distinguish between an absent web server and a missing web page on a web server.

Several reasons you get a 404 HTTP code are there in the realm of the internet; for instance, when the page was removed from the website, is one frequent trigger that prompts an error 404 message. If the page was relocated to another URL and the address was improperly redirected. If The user has typed incorrect URLs, then that can also prompt this. Even although it is exceedingly unusual, the server sometimes fails. The domain name entered no longer exists. Broken links often remain after the age has been removed or relocated for lengthy periods.

Intuitive navigation is one of the basic web design features. This is why an error 404 may be one of your visitors' most annoying things. If a visitor cannot access the material or page, he is searching for; he will probably abandon his webpage entirely and go to the site of a rival instead. Besides a terrible user experience, over 404 errors may damage the SEO efforts of your website, making search results less common. How? Google observes the high bounce rate — one meter, but rapidly, of visitors who come to your website. If you are badly designed and if there are many 404 errors, people will quit your website.


Have you ever been looking for information to visit a page to find just a 404 error? At that moment, what did you do? The odds are that you have closed the tab and searched for another site. This is how most Internet users conduct themselves. The more 404 pages you have, the less time people spend on your website. More and more users experience a mistake the longer you have a broken connection on your site. Special consideration is given to the compliance of users with the search engine Algorithms. In the rating process, their online conduct plays a crucial influence. And an HTTP 404 code is one of your visitors' most irritating experiences.

A few ways via which pages return 404 status codes can be accessed through the website. The constraint is that only links are available on one domain, and 404 links on other websites are ignored. As a consequence, 83% of 404 web pages lack these capabilities. An analysis of external links is a technique to detect 404 errors. One technique of finding 404 bugs is using Google Search Console, Google Analytics, or crawling tools. These tools might help you locate links inside a certain website. Tracking traffic using log file analysis to 404 pages is another frequent approach.


Some 404 errors are highly likely not to be detected on your website. Let us say that having a few broken links is typical before you start to concern yourself. A 404-page Not Found issue will occur sooner or later on most sites. However, it is always tracking and fixing that you should do. Correction of mistakes is critical to prevent consumers from meeting them as fast as feasible. Now the key part: How may an error 404 be fixed? Here's what you can do:

Remove the page

You may simply and easily redirect the website to another one to repair your 404 Error Code. This operation may be done by redirecting 301. Can you inquire what's 301? It is an answer code that redirects the browser to the effect of the content on another URL.

Fix the link

Irrigation is human. Therefore, errors can occur. People can mistype a URL sometimes. Make sure you go back to fix your URL if that is what happened to your 404 error code.


Website operators need to prevent HTTP 404 pages. This applies to internal 404 error pages on their website and external 404 error pages on other sites. There are numerous free tools available to help you find these broken links more easily. Three of the best and most well-known are:

Google Search Console (formerly known as 'Google Webmaster Tools'): if you already have a Google account and have registered your website there, you should use the Google Search Console option. Any 404 errors found by the Google crawler are displayed in the web tool and can also be marked as corrected.

Dead Link Checker: The Dead Link Checker is one of the most straightforward and quickest tools for discovering 404 pages both internally and outside. You input the website URL you wish to check using our web application and start the check. You may choose to examine a single website or a whole site here. The program shows all sites with status codes and URLs that are being monitored.

W3C Link Checker: this W3C Online tool is especially comprehensive in the examination of website pages so that the process of checking liaisons lasts longer than other sites. 

While an error on your site is not ideal, you can turn a negative into a positive. Many companies get creative with their 404 pages. Just don't forget to stick to your core color scheme — a 404 page is a great opportunity to showcase your brand's personality and make an impression on visitors. You could even incorporate links to other helpful content and resources or a call to action to help get the visitor on their way.

Some content management systems (CMS) like WordPress, Joomla, and Drupal automatically generate a 404 error page when a website’s URL can’t be found. The HTTP 404 page is just a simple standard error message, but most can be personalized using special CMS extensions. If your CMS doesn’t give you the option of creating or changing your 404 pages, or if your website is solely based on HTML, PHP, etc., it will prove a bit more complicated. You can create an error page as follows:


  • Creates an error page in the root directory ("404.html" or "404.php") (if one isn't already present).
  • In the root directory, type 'ErrorDocument 404 /404.html' to open the .htaccess file (or create one if required) and save your modification. This code generates the error page.
  • Try to access an inaccessible web page, and the 404 message error will hopefully be shown in the browser to see whether it works.


The error on your website is hard to avoid; to some extent, this is almost unavoidable: you will see 404 errors on your site. Make sure you proactively check the performance of your site to minimize SEO problems and poor user involvement. The HTTP 404 testing is just as important as publishing original content. Check your 404s every month, at least once, and every week if your site is larger. Setting time to update your website and conducting technical testing can help you stay ahead and interested in those people. The troubleshooting tools shall be extensively used for providing due care and caution to the website owners. Usage of these tools will make the website much more accessible, and this will help the users have a better experience.

Antoniy Yushkevych

Master of word when it comes to technology, internet and privacy. I'm also your usual guy that always aims for the best result and takes a skateboard to work. If you need me, you will find me at the office's Counter-Strike championships on Fridays or at a.yushkevych@monovm.com