What are Server Status Codes? HTTP Codes and Their Meaning

Server status codes are three-digit responses that describe the result of an HTTP request sent by a browser or other client. These status codes indicate whether a page was opened successfully, redirected to another address, or a code error occurred. HTTP status codes are classified under five basic categories between 100 and 599.

In terms of SEO, it is especially important to manage 3xx, 4xx and 5xx status codes correctly. For example, a deleted page constantly giving 404 may negatively affect the user experience, while incorrect redirects may make it difficult for search engines to crawl the site.

What Do HTTP Status Codes Mean?

To understand the question of what is an HTTP error, it is necessary to know that not all status codes are errors. Some codes indicate successful transactions, some indicate redirects, and some indicate actual errors.

The codes are basically divided into the following groups:

1xx – Information: Indicates that the request has been received and the operation is continuing.
2xx – Success: Indicates that the request has been completed successfully.
3xx – Redirect: Another action or redirect is required to reach the resource. Indicates.
4xx – Client errors: Indicates problems with the URL, access authorization, or the request sent.
5xx – Server errors: Indicates that the server was unable to complete a valid request.

Therefore, not all codes indicate a problem. For example, code 200 is a successful response, while 404 and 500 indicate error conditions.

Most Common Codes and Their Meanings

Some HTTP status codes occur more frequently than others in website administration:

200 OK: The request was completed successfully.
301 Moved Permanently: The resource is permanently moved to another location. moved to a URL.
302 Found: Indicates a temporary redirect.
400 Bad Request: The server was unable to process the submitted request.
401 Unauthorized: The user requires authentication.
403 Forbidden: The server understood the request but does not allow access to the resource.
404 Not Found: The requested resource or page could not be found.
429 Too Many Requests: Too many requests were sent in a short time.
500 Internal Server Error: A general error on the server occurred.
502 Bad Gateway: The proxy server received an invalid response from another server.
503 Service Unavailable: The server is temporarily unable to meet the request.
504 Gateway Timeout: The proxy server could not receive the required response in time.
505 HTTP Version Not Supported: The HTTP version used in the request is determined by the server. is not supported.

What Do 404 and 505 Mean?

The question of what 404 and 505 mean is important because although both codes are in the error group, they indicate different problems.

404 Not Found indicates that the server cannot find the requested resource. Misspelled URLs, removed pages, or addresses that have been changed without redirecting can cause a 404 error. In some cases, it may be more appropriate to use the 410 Gone code for a permanently removed resource.

505 means HTTP Version Not Supported. Indicates that the HTTP version used by the client in the request is not supported by the server.

Are Codes 56, 61, 111 and 125 HTTP Errors?

You may encounter different error searches on the Internet as 56 code, 61 code, 111 code or 125 code. However, each of these numbers is not a standard HTTP status code.

56 and 61 cannot be HTTP status codes because they are two digits. Although 111 and 125 are three digits, they are not among the assigned HTTP response codes in IANA's list of standard HTTP status codes. Such numbers may be error codes used by the operating system, connectivity software, API, application or a different service. Therefore, their meaning should be evaluated according to the system in which they appear.

Why Are Server Status Codes Important for SEO?

HTTP status codes help both users and search engine bots understand the current status of a page. Regular checking of removed pages, redirects and server errors is one of the important parts of technical SEO work.

For example, constantly redirecting non-working links to 404 pages can weaken the user experience. MDN also states that broken links can lead to a negative experience for users and should be reduced as much as possible.

Therefore, server status codes should be considered not only as a technical issue, but as an important control area that helps monitor site health and users' smooth access to pages.

Content was updated on October 2, 2026.