They are three-digit numbers returned by a web server to indicate the status of a requested HTTP (Hypertext Transfer Protocol) transaction.
These codes are a part of the HTTP protocol, and they help provide information about the outcome of the request made by a client (e.g., a web browser) to the server.
Each HTTP status code has a specific meaning and is grouped into different classes.
The error status messages are divided into 1xx, 2xx, 3xx, 4xx, 5xx.
See the below status codes and its causes.

Staus Code


100 Continue

The initial part of the request was received, and the client should proceed to send the remainder of the request.

101 Switching Protocols

The server agrees to switch protocols, as indicated by the Upgrade header sent in the request.

103 Early Hints

Used to return some response headers before the final HTTP message.

200 OK

The request was successful, and the server has returned the requested data.

201 Created

The request was successful, and a new resource was created as a result.

202 Accepted

The request was accepted for processing, but the processing is not yet complete.

203 Non-Authoritative Information

The server is a transforming proxy that received a 200 OK response from the origin, but is returning a modified version of the origin's response.

204 No Content

The request was successful, but there is no additional information to send in the response payload.

205 Reset Content

The request was successful, and the user agent should reset the document view that caused the request to be sent.

206 Partial Content

The server is delivering only part of the resource due to a Range header sent in the request.

300 Multiple Choices

Indicates multiple options for the resource from which the client may choose.

301 Moved Permanently

The requested resource has been permanently moved to a new URL.

302 Found (or Moved Temporarily)

The requested resource has been temporarily moved to a different URL.

303 See Other

The response to the request can be found under a different URL.

304 Not Modified

The requested resource has not been modified since the last request, and the response does not contain the requested data.

307 Temporary Redirect

The requested resource has been temporarily moved to a different URL, and the client should continue using the original URL for future requests.

308 Permanent Redirect

The requested resource has been permanently moved to a different URL, and the client should continue using the original URL for future requests.

400 Bad Request

The server cannot understand the request due to a client error or malformed syntax.

401 Unauthorized

The client must authenticate itself to get the requested response, and authorization has failed or has not been provided.

403 Forbidden

The client does not have permission to access the requested resource.

404 Not Found

The requested resource could not be found on the server.

405 Method Not Allowed

The requested method is not allowed for the specified resource.

406 Not Acceptable

The server cannot produce a response matching the list of acceptable values defined in the request's headers.

407 Proxy Authentication Required

The client must first authenticate itself with the proxy.

408 Request Timeout

The client did not produce a request within the time the server was prepared to wait.

409 Conflict

Indicates that the request could not be processed because of conflict in the request.

410 Gone

Indicates that the requested resource is no longer available and will not be available again.

411 Length Required

The server refuses to accept the request without a defined Content-Length.

412 Precondition Failed

The precondition given in the request evaluated to false by the server.

413 Payload Too Large

The server refuses to process the request because the request payload is larger than the server can process.

414 URI Too Long

The server refuses to service the request because the request-target is longer than the server is willing to interpret.

415 Unsupported Media Type

The server refuses to service the request because the entity of the request is in a format not supported by the requested resource.

416 Range Not Satisfiable

The client has asked for a portion of the file (byte serving), but the server cannot supply that portion.

417 Expectation Failed

The server cannot meet the requirements of the Expect request-header field.

429 Too Many Requests

The user has sent too many requests in a given amount of time.

500 Internal Server Error

The server encountered an unexpected condition that prevented it from fulfilling the request.

501 Not Implemented

The server does not support the functionality required to fulfill the request.

502 Bad Gateway

The server received an invalid response from an upstream server while trying to fulfill the request.

503 Service Unavailable

The server is currently unable to handle the request due to temporary overloading or maintenance of the server.

504 Gateway Timeout

The server, while acting as a gateway or proxy, 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 must authenticate to gain network access.

Quick Recap - Topics Covered

Status Catagory



Status Codes



These are provisional responses that indicate the server has received the request and is continuing to process it

100, 101, and 103



These codes indicate that the request was successfully received, understood, and accepted by the server

200, 201, 202, 203, 204, 205, and 206



These codes indicate that further action needs to be taken to complete the request, such as following a redirect

300, 301, 302, 303, 304, 307, and 308


Client error

These codes indicate that the client's request contains bad syntax or cannot be fulfilled, often due to an error on the client's side

400, 401, 402, 403, 404, 405, 406, 407, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417, and 429


Server error

These codes indicate that the server failed to fulfill a valid request. Server errors are typically due to issues on the server's side

500, 501, 502, 503, 504, 505, and 511

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