Regex & Testing

HTTP Status Codes

Complete HTTP status code reference. Search and filter all standard codes with descriptions, typical use cases, and cacheability notes.

Free Offline Reference All 60+ Codes Searchable
Code Name & Description Cache
1xx Informational
100
Continue
Server received request headers; client should proceed.
No
101
Switching Protocols
Server is switching protocol as requested.
No
102
Processing
Server has received and is processing the request.
No
103
Early Hints
Used to return response headers before final response.
No
2xx Success
200
OK
Standard success response for GET, POST, PUT, DELETE.
Conditional
201
Created
Resource successfully created (e.g. after POST).
No
202
Accepted
Request accepted but not yet complete (async processing).
No
203
Non-Authoritative Information
Response from a third-party source.
Conditional
204
No Content
Success but no body returned — common after DELETE.
No
205
Reset Content
Client should reset the document view.
No
206
Partial Content
Partial response for range requests.
Conditional
207
Multi-Status
Multiple statuses in body (WebDAV).
No
208
Already Reported
Members already enumerated (WebDAV).
No
226
IM Used
Response is result of instance manipulations.
Conditional
3xx Redirection
300
Multiple Choices
Multiple options for the resource.
Conditional
301
Moved Permanently
Resource permanently moved to new URL. SEO juice transfers.
Cacheable
302
Found
Temporary redirect. Original URL stays indexed.
No
303
See Other
Redirect to another URI using GET.
No
304
Not Modified
Resource not changed since last request; use cached version.
Cacheable
307
Temporary Redirect
Temporary redirect preserving request method.
No
308
Permanent Redirect
Permanent redirect preserving request method.
Cacheable
4xx Client Error
400
Bad Request
Malformed syntax or invalid request.
No
401
Unauthorized
Authentication required. Not logged in.
No
402
Payment Required
Reserved for future use (payment walls).
No
403
Forbidden
Authenticated but not permitted.
No
404
Not Found
Resource not found.
Conditional
405
Method Not Allowed
HTTP method not supported for this endpoint.
Cacheable
406
Not Acceptable
No content matching Accept headers.
No
407
Proxy Authentication Required
Client must authenticate with proxy.
No
408
Request Timeout
Server timed out waiting for request.
No
409
Conflict
Request conflicts with current resource state.
No
410
Gone
Resource permanently deleted (stronger than 404).
Cacheable
411
Length Required
Content-Length header missing.
No
412
Precondition Failed
Precondition in headers not met.
No
413
Content Too Large
Request body exceeds server limit.
No
414
URI Too Long
URI is too long for the server to process.
Conditional
415
Unsupported Media Type
Content-Type not supported.
No
416
Range Not Satisfiable
Range header cannot be satisfied.
No
417
Expectation Failed
Expect header expectation not met.
No
418
I'm a Teapot
An April Fools RFC. Any server must refuse to brew coffee with a teapot.
No
421
Misdirected Request
Request sent to wrong server.
No
422
Unprocessable Content
Validation errors (common in REST APIs).
No
423
Locked
Resource is locked (WebDAV).
No
424
Failed Dependency
Dependency of request failed (WebDAV).
No
425
Too Early
Server unwilling to risk processing early data.
No
426
Upgrade Required
Client must switch protocols.
No
428
Precondition Required
Conditional request required.
No
429
Too Many Requests
Rate limit exceeded.
No
431
Request Header Fields Too Large
Headers too large.
Conditional
451
Unavailable For Legal Reasons
Content blocked for legal reasons.
Conditional
5xx Server Error
500
Internal Server Error
Generic server error — check logs.
No
501
Not Implemented
Method not implemented by server.
Cacheable
502
Bad Gateway
Invalid response from upstream server.
No
503
Service Unavailable
Server temporarily unable to handle requests.
No
504
Gateway Timeout
Upstream server timed out.
No
505
HTTP Version Not Supported
HTTP version not supported.
No
507
Insufficient Storage
Server cannot store the representation (WebDAV).
No
508
Loop Detected
Infinite loop detected (WebDAV).
No
510
Not Extended
Further extensions required.
No
511
Network Authentication Required
Client needs to authenticate to access network.
No

Frequently Asked Questions

What do the HTTP status code ranges mean?
1xx (Informational) — request received, process continuing. 2xx (Success) — request successfully received, understood, and accepted. 3xx (Redirection) — further action needed. 4xx (Client Error) — request contains bad syntax or cannot be fulfilled. 5xx (Server Error) — server failed to fulfill a valid request.
What is the difference between 301 and 302?
301 (Moved Permanently) tells browsers and search engines the resource has permanently moved — they should update their bookmarks and SEO juice transfers. 302 (Found/Temporary Redirect) signals a temporary move — browsers redirect but search engines keep indexing the original URL.
What is the difference between 401 and 403?
401 (Unauthorized) means authentication is required — the client is not logged in. 403 (Forbidden) means the client is authenticated but does not have permission to access the resource.