Guide To Use Different Redirect 'Block, Redirect or Canonical' In Different Duplicate Content Cases

Duplicate content in search engine optimization (SEO) has been around for quite some time and Google has been been getting smarter in figuring out the best page to display in the SERPS from a list of duplicate content pages. Google claim its something less to worry about today, than before. But, they give advice from […]

Duplicate content in search engine optimization (SEO) has been around for quite some time and Google has been been getting smarter in figuring out the best page to display in the SERPS from a list of duplicate content pages. Google claim its something less to worry about today, than before. But, they give advice from various places: support threads, employee blogs, webmaster help videos, and many other places on how to fix this issue. Some say simply block your duplicate content pages, some say redirect them.

Maybe there's no 1 rule that best fits all situations, so here's a simply guide when to use which type of redirect in different cases of duplicate content:

  • Alternate Link Tag
    • International pages, multilingual pages, intended for different countries.
  • Canonical Link Tag
    • Multiple categories and subcategories with different category paths, but the same content.
      Example:
      http://www.example.com/products/laptops/sony/
      http://www.example.com/products/sony/laptops/
    • Tracking codes, Session IDs mainly because redirection sometimes interferes with the functionality of the tracking codes and sessions.
      Example:
      http://www.example.com/path/file.php?SID=BG47JF448JD6I7TGF439LVFD476
      http://www.example.com/path/file.php?utm_whatever=5uck3rs
      http://www.example.com/path/file.php
    • Different variable orders due to how some CMS platforms are created.
      Example:
      http://www.example.com/path/file.php?var1=x&var2=y
      http://www.example.com/path/file.php?var2=y&var1=x
  • 301 Redirect
    • Cases where a redirection doesn't bother the user experience such as www and non-www, index files, trailing slashes, hosting IP address.
      Example:
      http://www.example.com/
      http://example.com/
      http://www.example.com/index.html
      http://www.example.com
      http://123.123.123.123/
    • Domain changes, and URL changes of pages that no longer exist.
      Example:
      http://www.example.com/old_folder/old_file 301 redirects to http://www.example.com/new-folder/new-file/
      http://www.example.net/ 301 redirects to http://www.example.com/
  • Meta Robots NoIndex/Follow
    • Probably the best place to use this's in a list of archived post, such as a blog. Where the main URL of the individual blog post or the permalink may have content that is posted as a duplicate somewhere in the archive view by date, the category view, the author view, tag topic views, or in the pagination of older blog post from the blog homepage. You cann't really do a 301 redirect, nor do a canonical link tag since these pages may have more than 1 blog post listed and you'll have to finalized where the 301 redirect should go or where the canonical link tag should point to.
  • Robots.txt
    Probably this is one of the most common suggestion used by many people, including several people from Google. This would work in eliminating duplicate content. Search engine bots will see the robots.txt file and when it sees to exclude a URL of the hosted domain name, this URL is no longer crawled and indexed.

    Having said that, the only problem in using robots.txt in eliminating duplicate content is some people may be linking to the page that is excluded. That would prevent these links from contributing to your website's search engine ranking.

Duplicate Content & Multiple Site Issues:

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[tags]meta tags,link tags,canonical,categories,301 redirect,meta robots,noindex[/tags]

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