1xx (temporary response)

A status code that represents a temporary response and requires the requester to continue the operation.

Code description

100 (Continue) The requester shall continue to make the request. The server returns this code to indicate that the first part of the request has been received and is waiting for the rest.

101 (handover protocol) The requester has requested the server to switch the protocol, and the server has confirmed and prepared to switch.

2xx (successful)

Status code indicating that the request was processed successfully.

Code description

200 (Success) The server has successfully processed the request. Typically, this means that the server has provided the requested web page.

201 (Created) The request succeeded and the server created a new resource.

202 (Accepted) The server has accepted the request but has not yet processed it.

203 (Unauthorized information) The server has successfully processed the request, but the information returned may be from another source.

204 (No Content) The server successfully processed the request, but no content was returned.

205 (Reset Content) The server successfully processed the request but returned nothing.

206 (partial content) The server successfully processed some GET requests.

3xx (Redirect)

Indicates that further operations are required to complete the request. Typically, these status codes are used for redirection.

Code description

300 (Multiple choice) The server can perform multiple operations on the request. The server can select an operation according to the requester (user agent), or provide a list of operations for the requester to select.

301 (permanent move) The requested page has been permanently moved to a new location. When the server returns this response (a response to a GET or HEAD request), it will automatically move the requester to a new location.

302 (temporary move) The server currently responds to requests from web pages in different locations, but the requester should continue to use the original location for future requests.

303 (View other locations) This code is returned by the server when the requester should use separate GET requests for different locations to retrieve responses.

304 (unmodified) The requested page has not been modified since the last request. When the server returns this response, no web page content will be returned.

305 (Use Proxy) The requester can only use a proxy to access the requested web page. If the server returns this response, it also indicates that the requester should use a proxy.

307 (temporary redirection) The server currently responds to requests from web pages in different locations, but the requester should continue to use the original location for future requests.

4xx (request error)

These status codes indicate that the request may be in error, preventing the server from processing.

Code description

400 (Bad request) The server does not understand the syntax of the request.

401 (Unauthorized) Request requires authentication. The server may return this response for the webpage that needs to be logged in.

403 (Forbidden) The server rejects the request.

404 (not found) The server could not find the requested page.

405 (Method Disabled) Disables the method specified in the request.

406 (Unacceptable) Web pages that cannot respond to requests using the requested content attributes.

407 (proxy authorization is required) This status code is similar to 401 (unauthorized), but the designated requester should authorize the use of the proxy.

408 (request timeout) A timeout occurred while the server was waiting for a request.

409 (Conflict) The server encountered a conflict while completing the request. The server must include information about the conflict in the response.

410 (Deleted) If the requested resource has been permanently deleted, the server will return this response.

411 (Valid length required) The server does not accept requests that do not contain valid content length header fields.

412 (Prerequisite not met) The server does not meet one of the prerequisites set by the requester in the request.

413 (The request entity is too large) The server cannot process the request because the request entity is too large, which exceeds the server's processing capacity.

414 (The requested URI is too long) The requested URI (usually the web address) is too long for the server to process.

415 (Unsupported media type) The requested format is not supported by the requested page.

416 (The request range does not meet the requirements) If the page cannot provide the requested range, the server will return this status code.

417 (Expectations not met) The server did not meet the requirements of the Expectations request header field.

5xx (server error)

These status codes indicate that the server encountered an internal error while trying to process the request. These errors may be errors of the server itself, not request errors.

Code description

500 (internal server error) The server encountered an error and was unable to complete the request.

501 (not yet implemented) The server does not have the function to complete the request. For example, this code may be returned when the server does not recognize the request method.

502 (error gateway) server, as a gateway or proxy, received an invalid response from the upstream server.

503 (service unavailable) The server is currently unavailable (due to overload or downtime for maintenance). Usually, this is only a temporary state.

504 (gateway timeout) The server acts as a gateway or proxy, but does not receive requests from the upstream server in time.

505 (HTTP version is not supported) The server does not support the HTTP protocol version used in the request.