301, 302, 307 and 308 explained
301 and 308 are permanent redirects: search engines transfer signals to the new URL and replace the old one in results. 302 and 307 are temporary: the old URL may stay indexed. Use a permanent redirect whenever a page has moved for good.
308 and 307 keep the request method (for example POST), while 301 and 302 may change it to GET. For normal page moves, 301 is the standard choice.
Why redirect chains hurt
Every extra hop adds a network round trip for visitors and crawlers. Googlebot follows a limited number of hops in one go, and long chains often hide outdated rules from past migrations. Point each old URL straight at its final destination and update internal links to skip redirects entirely.
One version of your homepage
http://, https://, www and non-www are four different URLs to a search engine. Pick one, usually https with or without www, and permanently redirect the other three to it. Otherwise links and signals are split between duplicate versions of the whole site.
Frequently asked questions
Do redirects lose PageRank?
Google has said that 3xx redirects do not lose PageRank. Chains still cost crawl efficiency and speed, so keep them short.
Are meta refresh or JavaScript redirects OK?
Server-side 301 redirects are the most reliable. Meta refresh and JavaScript redirects are followed by Google but are slower and can confuse other crawlers.
How long should I keep redirects after a migration?
Keep them for at least a year, and ideally permanently for URLs that still receive links or traffic.