HTTP Codes
Status reference
HTTP Status Code Reference
Browse and search all HTTP status codes.
How to use the HTTP Codes tool
HTTP status codes are three-digit responses a web server sends for every request. They tell you whether a request succeeded, was redirected, or failed — and who is responsible. This reference lets you browse all common codes, filter by class (1xx to 5xx), and search by number or name, which is essential when debugging websites, APIs, and server configurations.
- 1 Browse the full list of HTTP status codes and their meanings.
- 2 Filter by class using the 1xx to 5xx buttons.
- 3 Search by code (404) or by description (redirect) to find the code you need.
Example: Search: 404
404
404 Not Found — the server cannot find the requested resource. A classic client error: the URL is wrong, moved, or removed.
HTTP Codes FAQ
What do the five HTTP status classes mean?
1xx is informational, 2xx means success, 3xx means redirection, 4xx is a client error (the request was bad), and 5xx is a server error (the server failed).
What is the difference between 301 and 302?
301 Moved Permanently tells browsers and search engines the page moved for good and should be replaced in indexes. 302 Found is a temporary redirect that keeps the original URL.
Why do I see 429 Too Many Requests?
429 means you have been rate limited: too many requests in a short window. Check the Retry-After header to see when you can try again, and add exponential backoff to your client.
What does 503 Service Unavailable mean for SEO?
It signals the server is temporarily overloaded or down for maintenance. Search engines usually retry later. For long maintenance windows, prefer a 503 with a Retry-After header over a 200 page that might be indexed.
