Understanding common HTTP errors is important for a happy and healthy website. Websites are made up of URLs, so it’s important to ensure that all of your URLs are working properly for optimum website health. In this post, we’re going to walk you through the most common server errors, and what to expect when you encounter one.

What are Server Status Codes?

Server status codes are used as a form of communication between the browser and the website’s server. For example, when you visit a website, your browser sends a request to the site’s server to which the server then responds with a three-digit code: the HTTP status code.

Common status code classes:

  • 1xxs – Informational responses: The server is thinking through the request.
  • 2xxs – Success: The server gave the browser the expected response.
  • 3xxs –Redirection: The request was received, but you’ve been redirected somewhere else.
  • 4xxs – Client errors: The request was made, but the page isn’t valid. There’s an error on the website’s side of the conversation and often appears when a page doesn’t exist on the site.
  • 5xxs – Server errors: A valid request was made by the client but the server failed to complete the request.

There are many different types of server status codes, so we’re going to stick to the ones most important for SEO. If you need a refresher on popular SEO terms, have a look through our glossary.

Server Status Codes for SEO

HTTP Status Code 200 – OK

This is the winner of all server status codes. It’s the status code for a properly functioning, normal page. Link equity — the power transmitted by all those hard-earned links to your content — passes through linked pages seamlessly, and you don’t need to worry about anything – your page is working just as it should be. 

HTTP Status Code 301 – Permanent Redirect

If you need to permanently redirect a URL to another, you should use a 301 redirect; both visitors and bots will be passed on to the new URL. A 301 redirect also passes link equity through to the new URL, and it’s the method we recommend for permanent page redirects.

Road sign showing 301 redirect server status code.
HTTP Status Code 302 – Temporary Redirect

When it comes to server status codes, a 302 redirect is similar to a 301. Although visitors and bots are transferred to the new page, link equity might not be. This is because search engine crawlers consider 302 redirects as temporary redirects. So, if you’re implementing a permanent redirect, a 301 is the way to go.

HTTP Status Code 404 – Page Not Found

404s are one of the most common HTTP errors, and it means the page that the browser is requesting wasn’t found by the server. If you search for a URL on your site that doesn’t exist, you’ll see a 404 in action. This is what visitors, and potential customers, will see if your page has a 404 error. It’s not ideal, and you couldn’t blame them for leaving your site to look for the answers or products elsewhere. So, we can all agree that understanding 404 server errors is vital!

As one of the most common HTTP errors, every site will have some pages with 404 status codes. Many people presume that it’s SEO best practice to 301 redirect pages that return 404 server errors to the site’s homepage. Unfortunately, this can actually confuse users as they may not realise the page they’re searching for doesn’t exist.

However, there are some instances where employing a 301 redirect works well. When it comes to 404 codes for high-performing pages – for example, pages with strong traffic flow or a high authority score – a 301 redirect to the most relevant page is a good option.

If you need a URL to return a 404 on purpose, for example, to stop them from being constantly crawled, you could create a custom 404 page to improve user experience.

404 server code drawing.
HTTP Status Code 410 – Gone

A 410 status code means that the page is no longer available from the server and no forwarding address has been set up. Internal links on your site directing to a 401 page are sending visitors (and bots) to a non-existent page. So, if you see any 410 server errors on your site, it’s best practice to remove any internal links directing to those pages.

HTTP Status Code 500 – Internal Server Error

A 500 is a classic server error and will affect access to your site. Both visitors and bots will become lost, and your link equity will become redundant. We definitely recommend fixing 500 server status codes as soon as possible because Google prefers well-maintained sites.  

HTTP Status Code 503 – Service Unavailable

503s are common HTTP errors where everyone is asked to return later. There are a few reasons why this could happen. For example, the server may be temporarily overloaded or under maintenance. 503 server status codes ensure that Google, and other search engines, know to return soon because the page is only going to be unavailable temporarily.

Navigating common HTTP errors can be complicated, but it’s super important to stay on top of them for your website’s functionality, visibility and user experience. At Zelst, our SEO team are experts in dealing with server errors and are happy to help you out with them. Just get in touch and we can start a conversation.