HTTP Response Codes

Introduction

When a Client  requests to a web server, Web Server Response to that request
IT can be an Internal Error , Client Error and ….. we Call it Response Code or  HTTP Status Message   .
It is common to name these errors HTML error messages.
But these messages are something called HTTP status messages. In fact, the server always returns a message for every request. The most common message is 200 OK.
Below is a list of HTTP status messages that might be returned:

1XX Information

Response Code
Reason
100 (Continue)
The server has received the request headers, and the client should proceed to send the request body
101 (Switching Protocols )
The requester has asked the server to switch protocols
103 (Checkpoint)
Used in the resumable requests proposal to resume aborted PUT or POST requests

2XX Successful

Response Code
Reason
200 (OK)
The request is OK (this is the standard response for successful HTTP requests)
201 (Created)
The request has been fulfilled, and a new resource is created
202 (Accepted)
The request has been accepted for processing, but the processing has not been completed
203 (Non-Authoritative Information)
The request has been successfully processed, but is returning information that may be from another source
204 (No Content)
The request has been successfully processed, but is not returning any content
205 ( Reset Content)
The request has been successfully processed, but is not returning any content, and requires that the requester reset the document view
206 (Partial Contentt)
The server is delivering only part of the resource due to a range header sent by the client

3XX Redirection

Response Code
Reason
300 ( Multiple Choices)
The request is OK (this is the standard response for successful HTTP requests)
301 ( Moved Permanently)
The request has been fulfilled, and a new resource is created
202 (Accepted)
The request has been accepted for processing, but the processing has not been completed
302 (Found)
The request has been successfully processed, but is returning information that may be from another source
303 (See Other)
The request has been successfully processed, but is not returning any content
304 (Not Modified)
The request has been successfully processed, but is not returning any content, and requires that the requester reset the document view
306 (Switch Proxy)
The server is delivering only part of the resource due to a range header sent by the client
307 (Temporary Redirect)
The server is delivering only part of the resource due to a range header sent by the client
308 (Resume Incomplete)
The server is delivering only part of the resource due to a range header sent by the client

4XX Client Error

Response Code
Reason
400 (Bad Request)
The request cannot be fulfilled due to bad syntax
401 (Unauthorized)
The request was a legal request, but the server is refusing to respond to it. For use when authentication is possible but has failed or not yet been provided
402 (Payment Required)
Reserved for future use
403 (Forbidden)
The request was a legal request, but the server is refusing to respond to it
404 (Not Found)
The request has been successfully processed, but is not returning any content
405 (Method Not Allowed)
A request was made of a page using a request method not supported by that page
406 (Not Acceptable)
The server can only generate a response that is not accepted by the client
407 (Proxy Authentication Required)
The client must first authenticate itself with the proxy
408 (Request Timeout)
The server timed out waiting for the request
409 (Conflict)
The request could not be completed because of a conflict in the request
410 (Gone)
The requested page is no longer available
411 (Length Required)
The "Content-Length" is not defined. The server will not accept the request without it
412 (Precondition Failed)
The precondition given in the request evaluated to false by the server
413 (Request Entity Too Large)
The server will not accept the request, because the request entity is too large
414 (Request-URI Too Long)
The server will not accept the request, because the URL is too long. Occurs when you convert a POST request to a GET request with a long query information
415 (Unsupported Media Type)
The server will not accept the request, because the media type is not supported
416 (Requested Range Not Satisfiable)
The client has asked for a portion of the file, but the server cannot supply that portion
417 (Expectation Failed)
The server cannot meet the requirements of the Expect request-header field

5xx: Server Error

Response Code
Reason
500 (Internal Server Error)
A generic error message, given when no more specific message is suitable
501 (Not Implemented)
The server either does not recognize the request method, or it lacks the ability to fulfill the request
502 (Bad Gateway)
The server was acting as a gateway or proxy and received an invalid response from the upstream server
503 (Service Unavailable)
The server is currently unavailable (overloaded or down)
504 (Gateway Timeout)
The server was acting as a gateway or proxy and did not receive a timely response from the upstream server
505 (HTTP Version Not Supported)
The server does not support the HTTP protocol version used in the request
511 (Network Authentication Required)
The client needs to authenticate to gain network access

2 thoughts on “HTTP Response Codes”

Leave a Comment