What is a 404 error? – SEO FAQs Simply Answered

Ever wonder what is a 404 error?

404 Error means that the page you were looking for was not found. Usually, it is for two reasons:

  • You inserted a wrong URL
  • The page has been removed.

What is a 404 error?

In more complex terms the 404 Not Found error message is a HTTP standard response code indicating that the client was able to communicate with a given server, but the server could not find what the requested resource.

Anytime you enter a URL into the browser a request is made on your behalf:

  1. The request is routed through the internet to the domain on the URL (e.g. www.techcrunch.com).
  2. The domain is converted to an IP.
  3. Your request goes through to that IP address.
  4. Once it reaches the computer on that IP address there is a web server listening.
  5. The web server will look for that resource and if it does not find it will send back a 404.

How to spot you came across 404 error page?

All of them tend to have similar properties:


what is a 404 error1


what is a 404 error2


what is a 404 error

As you can see, all of the 404 error pages indicates one thing – the page you are looking for, is not there.


How can you check how many 404 error pages site has?

There is no need to do it manually. There are several FREE tools that will automate finding 404 error pages.

My 3 favorite tools are:

  1. Broken Link Check
  2. Dead Link Checker
  3. Screaming Frog

What can you do when you see a 404 error?

Once you see a 404 error message, you should always double check the URL to make sure you are not the one making the mistake.

Once you know for sure it’s not your mistake. Almost 100% of the time the page has been moved or removed and webmaster has forgotten to add a redirect.

And Google hates that.

So, you should email the site’s owner and let him/her know that there is a 404 error on the page.

This is a great way of building relationships. You help a site owner out and you can be sure that sometime in the future the favor will be returned.

Who knows, maybe you will even get a backlink.

How to fix a 404 error?

If your own website has a 404 error page – there are few things that could have caused this and several ways how you can fix it.

If you edited the URL

This is the most common cause for a 404 error page. ALWAYS when you change the URL you have to create a redirect.

On WordPress there are several plugins that you can use that will automate redirect creation:

  1. Quick Redirects
  2. Redirection

If you are using a back-end (back-office) that doesn’t have an option to download a plugin. It will be a bit more difficult to create a redirect but you can watch the video below will guide you through the redirect creation process.

If you deleted the page

This can be tricky. If you deleted the page for some reason (you don’t need it, it doesn’t add value or it’s outdated) there are 2 things you can do.

The first option, 404 not found errors can indicate that there are still some resources that lead to this page – so you have to allocate these pages and ask the webmaster to remove the link or remove it by yourself where it’s possible.

The second option is to simply create a redirect using a suitable plugin or editing the code (more information in the “If you edited the URL” section).

What does HTTP error message mean?

There are 5 classes of standard HTTP response codes.

  1. 1xx – Informational Codes (gives provisional response)
  2. 2xx – Success Status Codes (tells request was received and processed successfully)
  3. 3xx – Redirection Status Codes (tells client to take additional action to complete request; used in URL Redirection)

The classes 4xx and 5xx are response codes for ERRORS.

  1. 4xx – Client Error
  2. 5xx – Server Error

4xx codes are used to tell the client that a fault has taken place on THEIR side. They should not retransmit the same request again but fix the error first.

5xx codes tell the client something happened on the server and their request by itself was perfectly valid. The client can continue and try again with the request without modification

I hope now you know what is a 404 not found error!

So to sum-up – 404 not found errors mainly appear in two cases:

  1. You inserted a wrong URL,
  2. OR the resource has been moved/removed.

If you can – message the site owners. That’s a nice thing to do 😉

Moreover, if you need more of your questions answered visit our SEO FAQ section.