HTTP Status Messages

Users may encounter errors when sending requests to a server. You have likely seen these messages frequently.

Here you can find the list of Hypertext Transfer Protocol (HTTP) response status codes. These codes are used to respond to the request of the client made to the server. There are 5 classes of HTTP response status codes. Let’s go through each class:

Danger

If you receive a response that is not included in this list, this means that it is a non-standard response, perhaps custom to the software of the server.

1xx: Information

Status code	Message	Description
100	Continue	Means that the server has received request headers and the client should continue to send request body.
101	Switching Protocols	Means that the client, who made a request, has asked the server to change protocols.
103	Checkpoint	Means that it is used in the resumable requests proposal to resume aborted PUT or POST requests.

2xx: Successful

Status code	Message	Description
200	OK	Means that the request is OK. It is standard response for successful HTTP requests.
201	Created	Means that the request has been fulfilled and a new resource is created.
202	Accepted	Means that the request has been accepted for processing, but the processing is going on.
203	Non-Authoritative Information	Means that the request has been successfully processed, but it is returning information which may be from another source.
204	No Content	Means that the request has been successfully processed, but it is not giving any content.
205	Reset Content	Means that the request has been processed, but it is not returning any content and it requires that the requester reset the document view.
206	Partial Content	Means that the server commits only a part of the resource, because of a range header, which was sent by the client.

3xx: Redirection

Status code	Message	Description
300	Multiple Choices	Indicates multiple options for the resource that the client may follow.
301	Moved Permanently	Means that the page has been moved to a new URL.
302	Found	Means that the requested page has been moved to a new URL temporarily.
303	See Other	Means that the requested page can be found in another URL.
304	Not Modified	Means that the requested page hasn't been modified since the last request.
306	Switch Proxy	Is not used anymore.
307	Temporary Redirect	Means that the requested page has been moved to a new URL temporarily.
308	Permanent Redirect	Means that the requested resource has been permanently moved to a new URL.

4xx: Client Error

Status code	Message	Description
400	Bad Request	Means that the request cannot be fulfilled due to bad syntax.
401	Unauthorized	Means that the request was valid, but the server refuses to respond. Used when authentication is required and has failed or has not yet been provided.
402	Payment Required	Is reserved for a future use.
403	Forbidden	Means that the request is valid, but the server refuses to respond.
404	Not Found	Means that the requested page cannot be found at the moment, but it may be available again in the future.
405	Method Not Allowed	Means that the request was made of a page that uses an unsupported request method for that page.
406	Not Acceptable	Means that the server can only generate an answer which the client doesn't accept.
407	Proxy Authentication Required	Means that the client first authenticate itself with the proxy.
408	Request Timeout	Means that the server timed out waiting for the request.
409	Conflict	Means that the request cannot be completed, because of a conflict in the request.
410	Gone	Means that the requested page is not available anymore.
411	Length Required	Means that the content length is not defined and the server won't accept the request without it.
412	Precondition Failed	Means that precondition, which is given in the request, is evaluated to false by the server.
413	Request Entity Too Large	Means that the request entity is too large and that's why the server won't accept the request.
414	Request-URI Too Long	Means that the URL is too long and that's why the server won't accept the request. It happens when you convert a POST request to a GET request with a long query information.
415	Unsupported Media Type	Means that the media type is not supported and that's why the server won't accept the request.
416	Requested Range Not Satisfiable	Means that the client asked for a part of the file but the server cannot supply that part.
417	Expectation Failed	Means that the server cannot meet the requirements of the expected request header field.

5xx: Server Error

Status code	Message	Description
500	Internal Server Error	Is a generic error and users receive this error message when there is no more suitable specific message.
501	Not Implemented	Means that the server doesn't recognize the request method or it lacks the ability to fulfill the request.
502	Bad Gateway	Means that the server was acting as a gateway or proxy and it received an invalid answer from the upstream server.
503	Service Unavailable	Means that the server is not available now (It may be overloaded or down).
504	Gateway Timeout	Means that the server was acting as a gateway or proxy and it didn't get answer on time from the upstream server.
505	HTTP Version Not Supported	Means that the HTTP protocol version, used in the request, is not supported by the server.
511	Network Authentication Required	Means that the client needs to authenticate to gain network access.

Practice

Which of the following are valid HTTP status codes according to the information available on w3docs.com?