HTTP 203 Non-Authoritative Information

What is HTTP 203 Non-Authoritative Information?

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 allows intermediaries to note that the content may differ from the original source.

Common Use Cases

• Proxy servers that modify content for optimization
• Content translation or transcoding services

// PHP - proxy returning 203 after modifying content
$originResponse = file_get_contents('https://origin.example.com/page');
$modified = minifyHtml($originResponse);

http_response_code(203);
header('Content-Type: text/html');
echo $modified;