HTTP 301 Moved Permanently vs 404 Not Found
HTTP 301 (Moved Permanently) is a 3xx Redirection response, while 404 (Not Found) is a 4xx Client Error response. 301 indicates 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. In contrast, 404 means that the server cannot find the requested resource. The URL may be wrong, the resource may have been deleted, or it may never have existed.
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.
Description
The server cannot find the requested resource. The URL may be wrong, the resource may have been deleted, or it may never have existed.
When You See It
When a URL is mistyped, a page has been deleted, or an API endpoint doesn't exist.
How to Fix
Verify the URL is correct. Check for typos, case sensitivity, and trailing slashes.
Key Differences
301 is a 3xx Redirection response, while 404 is a 4xx Client Error 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.
HTTP 404: The server cannot find the requested resource. The URL may be wrong, the resource may have been deleted, or it may never have existed.
You encounter 301 when after domain migrations, URL restructuring, or when consolidating duplicate URLs.
You encounter 404 when when a URL is mistyped, a page has been deleted, or an API endpoint doesn't exist.
When to Use Which
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. For 404 (Not Found): Verify the URL is correct. Check for typos, case sensitivity, and trailing slashes.