HTTP status 200 (OK) means a page was found and served successfully. Only 200 URLs should appear in the sitemap and serve as canonical targets.
(), also "200 OK", is a web server's standard response when a page exists and loaded successfully. It is the state that pages should return.
Status code 200 is central to clean and indexing:
Only canonical, indexable 200 URLs belong in the .
A should point to a reachable 200 page, not to a 404 or a .
Targets of 301 redirects should also return status 200.
An important special case is the : a page signals "not found" in its content but technically sends 200. This is problematic because search engines may interpret it as a valid page. Genuine error pages should send 404 or 410 instead.