A redirect sends visitors and search engines from one address to another. Redirects are normal after a redesign, a domain move or a change to https, but they often go wrong: a page redirects three times before it loads, two rules send a URL round in a loop, an old page lands on an error, or a temporary 302 is used where a permanent 301 was meant.
This checker follows each address you paste, hop by hop, and shows the status code at every step and where it ends. It points out loops, chains with more than one redirect, temporary redirects, changes between www and non-www, whether http moves to https, and the final status (200, 404, 410, 5xx). Addresses are checked one after another, a light HEAD request is used first, and a normal request is used if the server does not support HEAD. To keep the tool safe for everyone, it follows up to 5 hops and up to 20 addresses at a time.
Google’s guidance is to use permanent server-side redirects (301 or 308) when a page has moved for good, and to point old URLs straight at the final address rather than through a chain. Fixing chains also makes pages load a little faster for visitors.