HTTP 301 Moved Permanently for crawlers
301 Moved Permanently tells clients and crawlers that a resource has permanently moved to a new URL. It is the standard signal for migrations and URL changes: crawlers follow it, update their index over time, and consolidate ranking signals onto the new location. Use it whenever content has a stable new home.
What 301 means
301 Moved Permanently indicates the target resource has been assigned a new permanent URL given in the Location header. Compliant clients and crawlers should use the new URL for future requests. For search engines this is the canonical way to move a page and pass its accumulated signals to the new address.
Unlike a temporary redirect, 301 communicates permanence, so crawlers eventually drop the old URL in favour of the target.
Using 301 for migrations
When you change a URL structure, move to a new domain, or consolidate duplicate pages, map each old URL to its true equivalent with a 301. Redirecting everything to the homepage is a common mistake: an irrelevant target is treated like a soft 404 rather than a real move.
Keep redirects to a single hop. Chains (A to B to C) waste crawl budget and slow signal consolidation; loops break crawling entirely.
- Map each old URL to its real equivalent, not the homepage
- Prefer one hop; avoid A to B to C chains
- 301 is permanent — use 302/307 for temporary moves
Operator checklist
Confirm migrated URLs return 301 (not 302) to the correct target. Update internal links to point straight at the final URL so crawlers and users skip the redirect. Watch logs for old URLs still being crawled and for any redirect chains or loops.
How it appears in analytics and logs
A 301 in logs means the server is permanently redirecting a request to another URL. Crawlers follow it and, over repeated visits, replace the old URL with the target. A 301 pointing somewhere irrelevant behaves like a soft 404 and should be avoided.
Diagnostic use case
Migrate URLs or domains while preserving accumulated signals, and confirm crawlers are following the new location rather than hitting redirect chains or loops.
What WebmasterID can help detect
WebmasterID can surface which URLs return 301 to crawlers, helping you confirm a migration is redirecting correctly and spot old URLs still being crawled.
Common mistakes
- Using 302 for a permanent move, so signals are not consolidated.
- Redirecting all dead URLs to the homepage instead of a relevant target.
- Creating redirect chains or loops that waste crawl budget.
Privacy and accuracy notes
Redirect status codes are request-level signals with no personal data. WebmasterID reports redirect patterns for crawler traffic without exposing individual visitors.
Frequently asked questions
- Does a 301 pass ranking signals to the new URL?
- A 301 is the standard signal that a page has permanently moved, and search engines consolidate the old URL's signals onto the target over time. The redirect must point to a genuinely equivalent page, not an unrelated one.
Related pages
- HTTP 302 Found (temporary redirect)
302 Found signals a temporary redirect: the resource is briefly available at a different URL, but the original should still be used in future. Because it does not communicate permanence, crawlers keep the original URL. Using 302 for a permanent move is a common diagnostic problem.
- Redirect chains and loops
A redirect chain is a sequence of hops (A to B to C) before reaching the final URL; a redirect loop never resolves. Chains waste crawl budget, slow signal consolidation, and can stop crawlers following beyond a hop limit. The fix is to point each source straight at the final destination.
- Website observability
See which URLs return redirects to your traffic and crawlers.
Sources and verification notes
Last reviewed 2026-06-24. Facts are checked against primary/official sources where available; uncertain specifics are marked “Data not yet verified” rather than guessed.