HTTP 203 Non-Authoritative Information vs 301 Moved Permanently
HTTP 203 (Non-Authoritative Information) is a 2xx Success response, while 301 (Moved Permanently) is a 3xx Redirection response. 203 indicates that the response payload has been modified by a transforming proxy from the origin server's 200 response. In contrast, 301 means that the resource has been permanently moved to a new URL. All future requests should use the new URL. Search engines will transfer link equity to the new URL.
Description
The response payload has been modified by a transforming proxy from the origin server's 200 response.
When You See It
When a proxy or CDN modifies the response body (e.g., adds headers, transforms content).
How to Fix
Check if a proxy is modifying the response. Access the origin directly if you need the original content.
Description
The resource has been permanently moved to a new URL. All future requests should use the new URL. Search engines will transfer link equity to the new URL.
When You See It
After domain migrations, URL restructuring, or when consolidating duplicate URLs.
How to Fix
Update links and bookmarks to the new URL in the Location header. For SEO, this is the preferred redirect for permanent moves.
Key Differences
203 is a 2xx Success response, while 301 is a 3xx Redirection response.
HTTP 203: The response payload has been modified by a transforming proxy from the origin server's 200 response.
HTTP 301: The resource has been permanently moved to a new URL. All future requests should use the new URL. Search engines will transfer link equity to the new URL.
You encounter 203 when when a proxy or CDN modifies the response body (e.g., adds headers, transforms content).
You encounter 301 when after domain migrations, URL restructuring, or when consolidating duplicate URLs.
When to Use Which
For 203 (Non-Authoritative Information): Check if a proxy is modifying the response. Access the origin directly if you need the original content. For 301 (Moved Permanently): Update links and bookmarks to the new URL in the Location header. For SEO, this is the preferred redirect for permanent moves.