快速参考
About HTTP Status Codes
Encountering a 404 or 500 error can be confusing if you don't know what it means. Our free online HTTP Status Code reference provides clear, developer-friendly explanations for every standard HTTP response code.
How It Works
The tool provides a searchable, categorized database of all standard IANA-registered HTTP status codes. It breaks them down into five classes: Informational (1xx), Successful (2xx), Redirection (3xx), Client Error (4xx), and Server Error (5xx).
Common Use Cases
- Troubleshooting website errors and server misconfigurations
- Learning standard API response conventions for backend development
- Understanding SEO implications of different redirect codes (like 301 vs 302)
- Quickly looking up obscure status codes like 418 (I'm a teapot)
Frequently Asked Questions
A 4xx error means the client (your browser or app) did something wrong, like requesting a page that doesn't exist (404) or lacking permissions (403). A 5xx error means the server failed to fulfill a valid request due to an internal crash or overload (500).
Yes, HTTP status codes are a universal standard defined by the Internet Engineering Task Force (IETF) and are used by every web server on the internet.