HTTP status codes are standardized responses from a server to a client's request. They categorize the outcome of the request into five classes:
1xx: Informational
- 100 Continue: Client should continue sending data.
- 101 Switching Protocols: Server switches to a different protocol.
2xx: Success
- 200 OK: Request succeeded.
- 201 Created: Resource created successfully.
- 204 No Content: Request succeeded but no content returned.
3xx: Redirection
- 301 Moved Permanently: Resource permanently moved.
- 302 Found: Resource temporarily moved.
- 304 Not Modified: Resource unchanged since last request. 🔗 Learn more about redirection
4xx: Client Error
- 400 Bad Request: Invalid request syntax.
- 401 Unauthorized: Authentication required.
- 403 Forbidden: Permission denied.
5xx: Server Error
- 500 Internal Server Error: Unexpected server error.
- 502 Bad Gateway: Invalid response from upstream server.
- 503 Service Unavailable: Server temporarily overloaded.
For a visual comparison of status code categories, check our interactive chart. 📊