When your website request returns a 404 or 500, do you know its exact meaning and how to handle it? The HTTP Status Code Reference tool systematically organizes HTTP protocol response codes defined by IETF RFC standards. It breaks down every three-digit status code (e.g., 200, 301, 404, 500) into clear English and Chinese definitions, categories (1xx Informational, 2xx Success, 3xx Redirection, 4xx Client Error, 5xx Server Error), and their corresponding RFC specification sources.
Q: What is the difference between HTTP 404 and 410 status codes?
Both indicate client errors, but their semantics differ. 404 Not Found means the server cannot find the requested resource. 410 Gone explicitly states that the resource has been permanently deleted and will not be restored in the future. The 410 status code helps search engines update their indexes.
Q: What does "(RFC 7231)" next to a status code mean?
This indicates that the definition and specification of the status code originate from the RFC 7231 document published by the IETF. RFCs are internet technology standard documents; annotating the RFC number helps developers trace the most authoritative technical definitions.
This tool serves as a static reference manual and does not execute network request tests. Some status codes (like 306) have been deprecated by newer specifications but may still appear in legacy systems, so please be mindful of compatibility. The tool's information is based on public RFC standards; actual implementations may vary slightly depending on server, framework, or CDN configurations.
For developers, understanding status code categories is more important than memorizing individual codes. When encountering a 4xx error, prioritize checking the client request (URL, permissions, format). For 5xx errors, investigate server-side logic, dependent services, or resource limits. A typical example: uploading a file that is too large might return a 413 Payload Too Large, while a server processing timeout might return a 504 Gateway Timeout. We recommend using this tool as a quick reference guide alongside your browser's developer tools (Network panel) to diagnose network issues more efficiently.
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