Introduction to HTTP Status Codes – When you visit a website, your browser sends a request to the server. The server responds with an HTTP status code. These codes tell you if your request was successful or if there was an error.
Understanding HTTP status codes helps developers and website owners troubleshoot issues. This guide explains all the important codes in simple terms.
How HTTP Status Codes Work
HTTP status codes are 3-digit numbers. They are grouped into five categories:
- 1xx (Informational) – The request is being processed.
- 2xx (Success) – The request was successful.
- 3xx (Redirection) – The request needs further action.
- 4xx (Client Errors) – The request has an issue.
- 5xx (Server Errors) – The server failed to complete the request.
Let’s explore each category in detail.
1xx – Informational Status Codes
These codes show that the server is still processing the request.
- 100 Continue – The server has received the request headers.
- 101 Switching Protocols – The server agrees to switch protocols (e.g., from HTTP to WebSocket).
- 102 Processing – The server is working on the request but hasn’t finished yet.
These codes are rare for most users.
2xx – Success Status Codes
These mean the request was successful.
- 200 OK – The request worked perfectly. This is the most common success code.
- 201 Created – A new resource was successfully created (e.g., after a form submission).
- 202 Accepted – The request was accepted but not yet processed.
- 204 No Content – The request succeeded, but there’s no content to return.
A 200 status code is what every website aims for.
3xx – Redirection Status Codes
These codes mean the request must be redirected.
- 301 Moved Permanently – The page has moved to a new URL permanently.
- 302 Found (Temporary Redirect) – The page has moved temporarily.
- 304 Not Modified – The cached version of the page is still valid.
301 redirects are crucial for SEO when changing page URLs.
4xx – Client Error Status Codes
These errors occur due to client-side issues.
- 400 Bad Request – The server couldn’t understand the request.
- 401 Unauthorized – Login is required to access the resource.
- 403 Forbidden – The server refuses to respond (even if logged in).
- 404 Not Found – The requested page doesn’t exist.
- 429 Too Many Requests – The user sent too many requests in a short time.
A 404 error is common when a page is deleted or the URL is mistyped.
5xx – Server Error Status Codes
These mean the server failed to complete the request.
- 500 Internal Server Error – A generic server failure.
- 502 Bad Gateway – The server got an invalid response from another server.
- 503 Service Unavailable – The server is down for maintenance or overloaded.
- 504 Gateway Timeout – The server didn’t get a response in time.
A 503 status code often appears during website maintenance.
How to Fix Common HTTP Status Code Errors
Fixing 4xx Errors
- 404 Not Found: Check for broken links and set up redirects.
- 403 Forbidden: Verify file permissions on the server.
- 400 Bad Request: Ensure the request format is correct.
Fixing 5xx Errors
- 500 Internal Server Error: Check server logs for details.
- 502 Bad Gateway: Restart the server or check proxy settings.
- 503 Service Unavailable: Wait until maintenance is over or increase server capacity.
Why HTTP Status Codes Matter for SEO
Search engines like Google use HTTP status codes to crawl and index websites.
- 301 redirects pass SEO value to the new URL.
- 404 errors can hurt rankings if not fixed.
- 5xx errors may cause Google to temporarily stop crawling your site.
Fixing these errors improves user experience and SEO performance.
Conclusion
HTTP status codes are essential for website health. They help diagnose issues and improve performance.
Use this complete guide to HTTP status codes to troubleshoot errors and optimize your site. Bookmark it for quick reference!
By understanding these codes, you can keep your website running smoothly and ensure a better experience for users and search engines.
This guide provides accurate and easy-to-understand information on HTTP status codes. Follow best practices to maintain a healthy website.