Redirects
URL redirection is a process put in place to forward site visitors to an alternative page when the page they are looking to view is no longer live on the site. Redirects may be implemented for migration purposes, as well as for site re-architecture and when pages naturally expire. They can also be used to consolidate ranking signals. Our SEO Office Hours notes below cover the different redirection types and explore how Google understands these.
Further reading: The ABCs of HTTP Status Codes
Redirecting Robots.txt Is OK
Google will follow redirects for robots.txt files.
Redirect Desktop Users From AMP Pages to Desktop Pages
It’s not a problem to redirect non-mobile users from amp page to its desktop canonical but be careful when redirecting Googlebot desktop.
Redirect Chains Impact Usability and Crawling Efficiency
Google won’t penalise websites for having redirect chains but they can become a usability issue, particularly if they move between hostnames which can take longer. Google only crawls 5 redirects at a time, and will continue crawling a chain later on, but this many redirects should be avoided for any important URLs.
301 and 302 Redirects Only Determine Which URL is Indexed
A 301 indicates to Google that the destination URL should be indexed, a 302 indicates to Google that the original URL should be indexed but they always use the content on the destination page.
A High Volume of 301 Redirects is OK
John says millions of 301 redirects is OK and won’t affect your site.
Google Sometimes Makes Requsts with If-modified-since headers
Googlebot sometimes makes requests using an if-modificed-since request, in which case a 304 response is fine.
Use Redirects to Remove a Separate Mobile Site
If you are moving from a separate mobile site to a responsive site, redirect Mobile URLs back to Desktop and remove the rel alternate links from the desktop pages. You can use JavaScript redirects but it will take longer for Google to pick them up.
Redirects are Temporary or Permanent Based on Use
Google establishes temporary or permament redirects based on the situation which they are used instead of just looking at the status code, and they only really effect the URL which Google shows in results.
Automatic Geographic Redirects Should be Avoided
Googlebot should see the same redirects the same as normal users, so automatic redirects to a different geographic site should be avoided. Google only recommends a redirect from a generic page to a specific geographic site, or a pop-up to suggest a different geographic site to the one being used.
Google Might Show Redirected Domains
Google might display a redirected domain in search results for geo-specific queries.