100Continue
The client should continue with its request.
101Switching Protocols
The server is switching protocols as requested (e.g. to WebSocket).
103Early Hints
Preload hints sent before the final response.
200OK
The request succeeded.
201Created
The request succeeded and a new resource was created.
202Accepted
The request was accepted but not yet processed.
203Non-Authoritative Information
The returned metadata is from a copy, not the origin server.
204No Content
Success, but there is no content to return.
205Reset Content
Success; the client should reset the document view (e.g. clear a form).
206Partial Content
The server is delivering part of the resource (range request).
300Multiple Choices
The request has multiple possible responses to choose from.
301Moved Permanently
The resource has permanently moved to a new URL.
302Found
The resource is temporarily at a different URL.
303See Other
Follow a GET request to another URL to get the result.
304Not Modified
The cached version is still valid; nothing changed.
307Temporary Redirect
Temporary redirect that keeps the original method.
308Permanent Redirect
Permanent redirect that keeps the original method.
400Bad Request
The server could not understand the request (malformed syntax).
401Unauthorized
Authentication is required or has failed.
402Payment Required
Reserved for future use; sometimes used by paid APIs.
403Forbidden
The server understood but refuses to authorize the request.
404Not Found
The requested resource does not exist.
405Method Not Allowed
The HTTP method is not allowed for this resource.
406Not Acceptable
No response matches the client’s Accept headers.
407Proxy Authentication Required
You must authenticate with a proxy first.
408Request Timeout
The client took too long to send the request.
409Conflict
The request conflicts with the current state of the resource.
410Gone
The resource is permanently gone with no forwarding address.
411Length Required
The server requires a Content-Length header.
412Precondition Failed
A precondition in the request headers was not met.
413Content Too Large
The request body is larger than the server will accept.
414URI Too Long
The requested URI is longer than the server will accept.
415Unsupported Media Type
The request body’s media type is not supported by the server.
416Range Not Satisfiable
The requested range cannot be served.
417Expectation Failed
The Expect request header could not be met.
418I'm a teapot
An April Fools’ joke code — the server refuses to brew coffee.
421Misdirected Request
The request was sent to a server that cannot produce a response for it.
422Unprocessable Entity
The request was well-formed but has semantic errors (validation).
423Locked
The resource is locked (WebDAV).
425Too Early
The server is unwilling to risk processing a replayed request.
426Upgrade Required
The client should switch to a different protocol.
428Precondition Required
The server requires the request to be conditional.
429Too Many Requests
The client sent too many requests (rate limited).
431Request Header Fields Too Large
The request’s header fields are too large.
451Unavailable For Legal Reasons
The resource is unavailable for legal reasons (e.g. censorship).
500Internal Server Error
A generic server error with no more specific message.
501Not Implemented
The server does not support the functionality required.
502Bad Gateway
An upstream server returned an invalid response.
503Service Unavailable
The server is temporarily overloaded or down for maintenance.
504Gateway Timeout
An upstream server did not respond in time.
505HTTP Version Not Supported
The HTTP version used in the request is not supported.
507Insufficient Storage
The server cannot store the representation needed (WebDAV).
511Network Authentication Required
You must authenticate to gain network access (captive portal).
🔒 A static reference — nothing is uploaded.