Is it okay to keep old redirects or should they be eliminated?

• We have a variety of redirects we put in our sites over the years to keep Google and other search engines from seeing duplicate content. For instance, sitename.com redirects to www.sitename.com. We have an old one that directs from http to https and others that point from sitename.com/directory to sitename.com/directory/

  I need to know which redirects are really needed and which are ok to remove when you also have canonical link tags on all the pages?

Answer:

That being said, the redirects you've mentioned are structural redirects and should stay in place forever. For example, the canonical tag is just a recommendation to Google as to your preferred URL, it doesn't force them to do anything. Your hard 301 redirects do prevent spidering and indexing of the wrong URL structures.

Perhaps even more important, it helps keep the inbound links consistent. If someone can visit the site using multiple variations, you'll end up with inbound links in multiple variants, which in turn will reduce transferred Page rank if you have to redirect those URLs.

Here's the advice that Google still pushes to users on their Change page URLs with 301 redirects informational page. This focuses on best practices and how many are TOO many 301s for a website.

From our perspective, assuming they are free of errors, and you aren't overloaded with them - then we think keeping your hard redirects in place is a good idea. Our best practice rule is to keep them in place for at least a year and to check traffic before you remove them.

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