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HTTP Status Code Reference

Complete reference guide for HTTP status codes with descriptions and common use cases.

Status Code Information:

HTTP Status Code Classes

Class Range Description
1xx 100-199 Informational responses
2xx 200-299 Successful responses
3xx 300-399 Redirection messages
4xx 400-499 Client error responses
5xx 500-599 Server error responses

Common HTTP Status Codes

2xx Success

200 OK
The request was successful
201 Created
Resource created successfully
202 Accepted
Request accepted for processing
204 No Content
Success but no content to return

3xx Redirection

301 Moved Permanently
Resource moved permanently
302 Found
Resource temporarily moved
303 See Other
See other resource
304 Not Modified
Resource not modified

4xx Client Error

400 Bad Request
Invalid request syntax
401 Unauthorized
Authentication required
403 Forbidden
Access denied
404 Not Found
Resource not found
405 Method Not Allowed
HTTP method not allowed
408 Request Timeout
Request timed out
429 Too Many Requests
Rate limit exceeded

5xx Server Error

500 Internal Server Error
Unexpected server error
501 Not Implemented
Feature not implemented
502 Bad Gateway
Invalid gateway response
503 Service Unavailable
Service temporarily unavailable
504 Gateway Timeout
Gateway timeout

HTTP Status Code Categories

1xx Informational

These status codes indicate that the server has received the request and is continuing to process it. They are primarily used for communication between the server and client during request processing.

  • 100 Continue: Server received request headers, client should continue
  • 101 Switching Protocols: Server switching protocols as requested
  • 102 Processing: Server processing request (WebDAV)

2xx Success

These status codes indicate that the client's request was successfully received, understood, and accepted.

  • 200 OK: Standard success response
  • 201 Created: Resource successfully created
  • 202 Accepted: Request accepted for processing
  • 203 Non-Authoritative: Response from cached copy
  • 204 No Content: Success with no content returned
  • 205 Reset Content: Reset document view
  • 206 Partial Content: Partial content returned

3xx Redirection

These status codes indicate that further action is needed to complete the request, typically a redirect to another URL.

  • 300 Multiple Choices: Multiple options available
  • 301 Moved Permanently: Resource moved permanently
  • 302 Found: Resource temporarily moved
  • 303 See Other: See other resource (GET request)
  • 304 Not Modified: Resource not modified since last request
  • 305 Use Proxy: Use proxy (deprecated)
  • 307 Temporary Redirect: Temporary redirect (same method)
  • 308 Permanent Redirect: Permanent redirect (same method)

4xx Client Error

These status codes indicate that there was an error with the client's request.

  • 400 Bad Request: Malformed request syntax
  • 401 Unauthorized: Authentication required
  • 402 Payment Required: Payment required
  • 403 Forbidden: Access denied
  • 404 Not Found: Resource not found
  • 405 Method Not Allowed: HTTP method not supported
  • 406 Not Acceptable: Content not acceptable
  • 407 Proxy Authentication: Proxy authentication required
  • 408 Request Timeout: Request timed out
  • 409 Conflict: Request conflicts with current state
  • 410 Gone: Resource no longer available
  • 411 Length Required: Content-Length header required
  • 412 Precondition Failed: Precondition failed
  • 413 Payload Too Large: Request entity too large
  • 414 URI Too Long: URI too long
  • 415 Unsupported Media Type: Media type not supported
  • 416 Range Not Satisfiable: Range not satisfiable
  • 417 Expectation Failed: Expectation failed
  • 418 I'm a teapot: April Fools' joke (RFC 2324)
  • 422 Unprocessable Entity: Semantic errors in request
  • 425 Too Early: Too early to process
  • 426 Upgrade Required: Protocol upgrade required
  • 428 Precondition Required: Precondition required
  • 429 Too Many Requests: Rate limit exceeded
  • 431 Request Header Too Large: Header too large

5xx Server Error

These status codes indicate that the server encountered an error while processing the request.

  • 500 Internal Server Error: Unexpected server error
  • 501 Not Implemented: Feature not implemented
  • 502 Bad Gateway: Invalid gateway response
  • 503 Service Unavailable: Service temporarily unavailable
  • 504 Gateway Timeout: Gateway timeout
  • 505 HTTP Version Not Supported: HTTP version not supported
  • 506 Variant Also Negotiates: Variant negotiation error
  • 507 Insufficient Storage: Insufficient storage
  • 508 Loop Detected: Infinite loop detected
  • 510 Not Extended: Further extensions required
  • 511 Network Authentication Required: Network authentication required