Soft 404
A URL that returns HTTP 200 while displaying content that means 'not found' or has no real content, causing search engines to treat it as…
TechnicalResponse codes
HTTP status codes
Numeric codes in an HTTP response that tell crawlers how to treat a URL: 200 index it, 3xx follow the redirect, 404/410 drop it, 5xx come back later.
In full
Google treats 200 as indexable, 301/308 as permanent moves that consolidate signals, 302/307 as temporary, 404 and 410 as gone (410 slightly faster to drop), 429 and 503 as back-off signals, and other 5xx as errors that reduce crawl rate. Serving the wrong code is a frequent bug: 200 on missing pages creates soft 404s, and 503 left in place for weeks eventually causes deindexing. Codes are also what redirect chains and loops are diagnosed with.
Example
During a two-hour deploy, a site returns 503 with a `Retry-After` header so Googlebot pauses rather than recording thousands of errors.
Related terms
301 redirect
A server-side permanent redirect that tells crawlers a URL has moved for good and that ranking signals should consolidate on the…
302 redirect
A temporary redirect indicating the resource lives elsewhere for now; the original URL is expected to remain the canonical one.
Crawl rate limit
The maximum simultaneous connections and fetch frequency a crawler will use for a host, adjusted automatically based on server response…
Site migration
Any change to a site's domain, URL structure, platform, template or content organisation that materially affects how search engines see it.
Where to read more
- How HTTP Status Codes Affect Google's Crawlers · Documentation · developers.google.com
- MDN: HTTP Response Status Codes · Documentation · developer.mozilla.org