The reference desk — standardized codes, filed & searchableN° 2,372 entries · 11 collections ·
DirectoryCodes
The directory of the world’s codes

Front desk · HTTP Status Codes

4×× Client Error

406 Not Acceptable

HTTP 406 Not Acceptable is a client error-class status code defined in RFC9110. No content matching the request's Accept headers is available.

Client-error responses signal that the problem is on the requesting side: the request is malformed, unauthorized, or aimed at something that isn't there. On the wire, the response begins with the status line HTTP/1.1 406 Not Acceptable.