Google has stated that they will follow redirects up to a certain point. This experiment aims to find out a bit more about how far Google will go.
It's a simple experiment where the below link redirects forever. By tracking Googlebot activity I can find out how many of the redirects Google has followed, how frequently they are crawled, and how long it takes to get to a certain point.
The Chrome browser stops at 21 redirects (so does my Android browser), Firefox hit 20, Edge did 110 while IE won at 111 redirects!
My first go with submitting the test link for indexing caused a very quick crawl of 20 redirects. The next day I had a second go, this time the crawling was slower, with a few seconds between redirects, and it still made 20 redirects.
The link below is the test link. It will 301 redirect forever, each time incrementing the number in the destination URL. If you click on it in your browser you will get a too many redirects error, and the number in the address bar is how many redirects were followed before the error.Infinite Redirect Test Link
Update - 2016-11-13
Since the initial test Googlebot and the Smartphone bot have recrawled several times, each time reaching 20 redirects. The Smartphone bot has also continued on to crawl up to the 36th redirect. It looks like it is possible to get pages found that are behind a lot of redirects!