407 Proxy Authentication Required
This is an educational reference page about HTTP 407 Proxy Authentication Required. The page itself is served as 200 OK so it can be indexed as HTTP documentation.
The client must first authenticate itself with the proxy.
Specification
Registered in the IANA HTTP Status Code Registry as Proxy Authentication Required. Defined in RFC 9110, Section 15.5.8.
Header and content rules
What RFC 9110 says about a 407 response, quoted from the RFC. The 4xx class rules also apply.
- MUST (proxy; Proxy-Authenticate): Send Proxy-Authenticate with a challenge for that proxy. Table row
The proxy MUST send a Proxy-Authenticate header field (Section 11.7.1) containing a challenge applicable to that proxy for the request. RFC 9110 §15.5.8
The same rule is in the response obligations table and its JSON.