HTTP status codes are messages sent from a website's server to the browser, indicating whether a request can be fulfilled. Defined by the W3C, these codes are included in the HTTP header of a page to inform the browser of the outcome of its request.
When everything works as expected, the server responds with a 200 status code. However, various issues can arise when attempting to fulfill a browser's request to the server. HTTP status codes are grouped into five ranges. Each range indicates where the issue occurred, while the specific number explains the exact nature of the response or error.
Here’s a breakdown of the five ranges and their meanings:
1xx: Informational – The request was received, and the process is continuing.
2xx: Success – The request was successfully received, understood, and processed.
3xx: Redirection – The requested resource has been moved to a different location.
4xx: Client Error – There was an issue with the request made by the browser.
5xx: Server Error – The server encountered a problem while trying to fulfill the request.
Why HTTP status codes are important for SEO
HTTP status codes play a critical role in SEO as they directly impact how search engines crawl and interact with your website. Here's why they are important:
1. Crawling and Indexing
Search engine bots rely on HTTP status codes to understand how to process a website’s content:
2xx (Success): Indicates that pages are accessible, making them eligible for indexing.
3xx (Redirects): Proper use of redirects helps bots locate and index the correct page. Misconfigured redirects (e.g., redirect chains or loops) can lead to poor crawling and loss of link equity.
4xx (Client Errors): Broken links or "404 Not Found" errors signal a poor user experience, potentially leading to de-indexing of affected pages.
5xx (Server Errors): Persistent server issues can prevent search engines from crawling your site, harming rankings.
2. User Experience
Search engines prioritize websites that offer seamless user experiences. Incorrect or excessive status code errors can frustrate users, leading to high bounce rates, which negatively influence SEO performance.
3. Link Equity Preservation
Redirects (3xx) ensure that link equity (ranking power from backlinks) is passed to the correct pages. For example, using a 301 (Permanent Redirect) helps transfer SEO value to a new page after URL changes.
4. Site Health Monitoring
Frequent or widespread HTTP errors signal issues with a website’s structure or server performance. Search engines may lower the rankings of websites with recurring technical problems.
5. Canonicalization and Duplicate Content
Proper status codes help search engines understand the preferred version of a page, especially with 301 redirects or 200 (OK) codes for canonical pages. This minimizes the risk of duplicate content penalties.
How to Check The Returned Status Code for your page
Google developer tools are the direct way to check on the returned http status code. Simply, with the right click on the page, go to "inspect" , and then check the network tab. The first line indicates the returned status code.
Also you can use some chrome extensions like Redirect path to directly check the status codes. The extension is mainly useful to see all the returned codes when multiple redirects are implemented.
For a bulk analysis, tools like screaming frog can directly provide all the status codes with their further details.
Most Common HTTP Status Codes Every SEO Should Know
Here is the list of the most common HTTP status codes, and we will explain what every status code means:
Status code | Meaning |
| |
100 | Continue |
101 | Switching protocols |
102 | Processing |
103 | Early Hints |
| |
200 | OK |
201 | Created |
202 | Accepted |
203 | Non-Authoritative Information |
204 | No Content |
205 | Reset Content |
206 | Partial Content |
207 | Multi-Status |
208 | Already Reported |
226 | IM Used |
| |
300 | Multiple Choices |
301 | Moved Permanently |
302 | Found (Previously "Moved Temporarily") |
303 | See Other |
304 | Not Modified |
305 | Use Proxy |
306 | Switch Proxy |
307 | Temporary Redirect |
308 | Permanent Redirect |
| |
400 | Bad Request |
401 | Unauthorized |
402 | Payment Required |
403 | Forbidden |
404 | Not Found |
405 | Method Not Allowed |
406 | Not Acceptable |
407 | Proxy Authentication Required |
408 | Request Timeout |
409 | Conflict |
410 | Gone |
411 | Length Required |
412 | Precondition Failed |
413 | Payload Too Large |
414 | URI Too Long |
415 | Unsupported Media Type |
416 | Range Not Satisfiable |
417 | Expectation Failed |
418 | I'm a Teapot |
421 | Misdirected Request |
422 | Unprocessable Entity |
423 | Locked |
424 | Failed Dependency |
425 | Too Early |
426 | Upgrade Required |
428 | Precondition Required |
429 | Too Many Requests |
431 | Request Header Fields Too Large |
451 | Unavailable For Legal Reasons |
| |
500 | Internal Server Error |
501 | Not Implemented |
502 | Bad Gateway |
503 | Service Unavailable |
504 | Gateway Timeout |
505 | HTTP Version Not Supported |
506 | Variant Also Negotiates |
507 | Insufficient Storage |
508 | Loop Detected |
510 | Not Extended |
511 | Network Authentication Required |
And here are the most popular status codes that you will face during day to day tasks:
1xx: Informational
100 (Continue): The server has received the request headers, and the client can proceed with sending the body. Rarely relevant for SEO.
2xx: Success
200 (OK): The page loaded successfully, meaning it is accessible to users and search engines.
204 (No Content): The request was successful, but the server returned no content, potentially signaling an issue for indexable pages.
3xx: Redirection
301 (Moved Permanently): Indicates a permanent redirect to a new URL, passing almost all link equity and essential for URL changes.
302 (Found/Temporary Redirect): A temporary redirect, which does not transfer link equity permanently. Use carefully to avoid confusing search engines.
4xx: Client Errors
404 (Not Found): The requested page doesn't exist, leading to broken links. Too many 404s harm user experience and SEO.
410 (Gone): Signals the page is permanently removed and won't return, useful for intentional page removal.
5xx: Server Errors
500 (Internal Server Error): A general server issue preventing the page from loading. Persistent 500 errors harm crawling and indexing.
503 (Service Unavailable): Indicates the server is temporarily unavailable, often used during maintenance. Inform search engines if it's a temporary issue.
HTTP Status Codes SEOs Should Not Ignore and How to Fix Them
1. 4xx Client Errors
404 (Not Found): Indicates that the requested page doesn’t exist.
Why it matters: Broken links or missing pages harm user experience and result in loss of link equity.
How to fix:
Redirect to a relevant page using a 301 redirect.
If the page was removed intentionally, return a 410 Gone status.
Regularly monitor your website for broken links using tools like Google Search Console or Screaming Frog.
410 (Gone): Shows the page is permanently removed.
Why it matters: Similar to 404 errors, but signals intentional removal, which is clearer for search engines.
How to fix:
Redirect users to a replacement page if applicable.
Only use 410 for pages you do not want to be indexed or recovered.
2. 3xx Redirect Errors
301 (Moved Permanently): A permanent redirect to a new URL.
Why it matters: Helps transfer link equity and maintain rankings when URLs change.
How to fix:
Verify that the redirect points to the correct destination.
Avoid redirect chains (multiple redirects in sequence) and loops.
302 (Found/Temporary Redirect): A temporary redirect that does not transfer link equity.
Why it matters: Using 302 instead of 301 for permanent changes can confuse search engines.
How to fix:
Use 301 redirects for permanent changes unless the move is truly temporary.
3. 5xx Server Errors
500 (Internal Server Error): Indicates a problem with the server.
Why it matters: Prevents search engines from accessing your site, leading to de-indexing over time.
How to fix:
Check server logs to identify the issue.
Work with your hosting provider or developer to resolve server misconfigurations or code errors.
503 (Service Unavailable): Shows the server is temporarily down for maintenance.
Why it matters: If not handled properly, search engines may assume your site is unreliable.
How to fix:
Use the Retry-After header to inform search engines when the site will be back online.
4. Mixed Signals in Status Codes
Canonical Tags with 404 or 301 Redirects: Signals conflict in URL preferences.
How to fix: Ensure the canonical tag points to a live and accessible page.
Key Takeaways
To ensure you are correctly managing the status codes of your site, here are the final recommendations:
Regularly audit your website using tools like Google Search Console, Screaming Frog, or SEMrush to identify errors.
Set up server monitoring to catch and resolve 5xx errors quickly.
Plan and implement proper redirects during website migrations or restructuring.
By proactively addressing these status codes, SEOs can protect rankings, improve user experience, and ensure efficient crawling and indexing.
Comentários