505
HTTP Version Not Supported
Server errors (5xx)·RFC 9110
What 505 means
The server does not support the HTTP protocol version used in the request.
Rare in practice; the client should retry with a supported HTTP version.
Server errors (5xx)
The server failed to fulfil an apparently valid request.
Other 5xx codes
FAQ — 505
What does HTTP 505 mean?
505 HTTP Version Not Supported: The server does not support the HTTP protocol version used in the request. Rare in practice; the client should retry with a supported HTTP version.
Which class does status code 505 belong to?
505 is a Server errors (5xx) code. The server failed to fulfil an apparently valid request.
Where is the 505 code defined?
Status code 505 is defined in RFC 9110 and is part of the IANA HTTP Status Code Registry.