HTTP Status Codes

Web Server58 error codes

Reference list of 58 HTTP status codes with meanings, common causes, and related context.

Severity

Showing 58 of 58 error codes

500
High

Internal Server Error — the server hit an unexpected condition while handling the request

4 common causes
501
High

Not Implemented — the server does not support the HTTP method used in the request

3 common causes
502
High

Bad Gateway — the server received an invalid response from an upstream server

4 common causes
503
High

Service Unavailable — the server is temporarily unable to handle this request

4 common causes
504
High

Gateway Timeout — the gateway did not receive an upstream response in time

4 common causes
507
High

Insufficient Storage — the server lacks space to complete the request

3 common causes
508
High

Loop Detected — the server found an infinite processing loop while handling the request

3 common causes
400
Medium

Bad Request — the server cannot process the request because it is malformed

4 common causes
401
Medium

Unauthorized — valid authentication credentials are missing for the target resource

4 common causes
403
Medium

Forbidden — the server understood the request but refuses to authorize it

4 common causes
404
Medium

Not Found — the server cannot find the requested resource at this URL

4 common causes
405
Medium

Method Not Allowed — the resource exists but does not accept this HTTP method

4 common causes
407
Medium

Proxy Authentication Required — client must authenticate with a proxy before forwarding the request

3 common causes
408
Medium

Request Timeout — the server did not receive a complete request in time

4 common causes
409
Medium

Conflict

3 common causes
410
Medium

Gone — the requested resource was intentionally removed and is no longer available

4 common causes
411
Medium

Length Required — the server requires a valid Content-Length header

3 common causes
412
Medium

Precondition Failed — a conditional header did not match current resource state

3 common causes
413
Medium

Content Too Large — the request body is larger than the server allows

4 common causes
414
Medium

URI Too Long — the requested URL exceeds the server length limit

4 common causes
415
Medium

Unsupported Media Type — the request body format is not accepted here

4 common causes
417
Medium

Expectation Failed — the server cannot satisfy the request's Expect header requirements

3 common causes
421
Medium

Misdirected Request — the request reached a server that cannot answer for that authority

3 common causes
422
Medium

Unprocessable Content — the server understood the request but cannot apply its instructions

4 common causes
423
Medium

Locked

3 common causes
424
Medium

Failed Dependency — the request depends on another action that did not succeed

3 common causes
425
Medium

Too Early — the server rejects the request before replay-sensitive processing begins

3 common causes
428
Medium

Precondition Required — the server requires a conditional request before changing state

3 common causes
429
Medium

Too Many Requests — the client exceeded the allowed request rate

4 common causes
431
Medium

Request Header Fields Too Large — the header section exceeds accepted size limits

4 common causes
451
Medium

Unavailable For Legal Reasons — the server legally cannot serve the resource

4 common causes
506
Medium

Variant Also Negotiates — the selected representation has a circular negotiation configuration

3 common causes
511
Medium

Network Authentication Required — the client needs to authenticate to gain network access

3 common causes
100
Low

Continue — the server has received the request headers and the client should proceed

3 common causes
101
Low

Switching Protocols — the server is switching to the protocol requested by the client

3 common causes
103
Low

Early Hints — the server is sending preliminary response headers before the final response

3 common causes
200
Low

OK — the request succeeded and the server returned the expected response

3 common causes
201
Low

Created — the request was successful and a new resource was created

3 common causes
202
Low

Accepted — the request has been accepted for processing, but is not yet complete

3 common causes
203
Low

Non-Authoritative Information — the response was modified by an intermediate proxy

3 common causes
204
Low

No Content — the request was successful but there is no content to return

3 common causes
205
Low

Reset Content — the server asks the client to reset the document view

3 common causes
206
Low

HTTP 206 Partial Content — the server is sending a requested range

3 common causes
207
Low

Multi-Status — the response contains status information for multiple resources

3 common causes
226
Low

IM Used — the server fulfilled a delta-encoding request for the resource

3 common causes
300
Low

Multiple Choices — the request has more than one possible response representation

3 common causes
301
Low

Moved Permanently — the requested resource has been assigned a new permanent URL

4 common causes
302
Low

Found — the resource temporarily resides under a different URL

4 common causes
303
Low

See Other — the response is available at a different URL via GET

3 common causes
304
Low

Not Modified — the stored representation is still current, so no body is sent

4 common causes
307
Low

Temporary Redirect — the resource temporarily resides at a different location

4 common causes
308
Low

Permanent Redirect — the resource was permanently moved without method changes

4 common causes
402
Low

Payment Required

3 common causes
406
Low

Not Acceptable — the server cannot produce a response matching the request headers

3 common causes
416
Low

Range Not Satisfiable — the server cannot fulfill the byte range specified in the request

3 common causes
418
Low

I'm a teapot — the server refuses to brew coffee in a teapot

3 common causes
426
Low

Upgrade Required — the server demands a different protocol before continuing

3 common causes
505
Low

HTTP Version Not Supported

3 common causes