HTTP 203 Non-Authoritative Information
The response has been modified by a proxy or intermediate server.
2xx Success
203
Non-Authoritative Information
Description
The 203 Non-Authoritative Information status code indicates that the request was successful but the enclosed payload has been modified from that of the origin server's 200 OK response by a transforming proxy. This status code allows the proxy to notify recipients when a transformation has been applied, since that knowledge might impact later decisions regarding the content. For example, future cache validation requests for the content might only be applicable along the same request path (through the same proxies). It is commonly used when a proxy modifies headers or transforms content.
When Is It Used?
Used by proxies or CDNs when they modify the response from the origin server. For example, a proxy might compress the response, add headers, or transform content before forwarding it to the client.
Example Response
HTTP/1.1 203 Non-Authoritative Information
Content-Type: text/html
Via: 1.1 proxy.example.com