Here are some examples we’ve seen:
• Printer-friendly versions of pages.
• Old versions of pages that exist at old URLs.
• A pointer domain, also called a masked domain, which redirects site visitors
but hides the fact that they have been redirected by keeping the original domain
name in the browser address bar.
• Several different URLs for the same product, generated by an e-commerce
system.
• Duplicate categories within your store. For example, if you have separate categories
for “all neckties” and “men’s neckties,” they may display exactly the same
list of products on different URLs.
• Pages with various tracking tags (for example, &affiliate-id=3) tacked onto
the URLs.
• Pages that display with URLs in lowercase letters and also display using capital
letters.
• Articles or press releases that are reprinted from elsewhere on the Web.
If any of these situations sound familiar, don’t panic. We said search engines
don’t like duplicate content—we didn’t say they hate it the way they hate spam tactics.
Google, for example, is likely to choose its favorite page from among the clones and
filter the rest out of its index. According to Google, link authority will be consolidated
onto the favored version of the page, but this is one of those practices that the search
engines haven’t perfected yet. Possible disadvantages to letting the search engines see
duplicate content include the following:
• Your page authority could be diluted between all the multiple versions of your
pages.
• Search engine spiders will waste precious indexing time on all of those duplicates
and may miss out on indexing better parts of your site.
• Worst-case scenario: If search engines run into a large amount of duplicate content
on your site, they may stop, or slow, your website indexing.
If the extent of duplicate content on your site is a few pages here and there, you
probably don’t need to worry about it.
Duplicate Pages Solution
Canonical Tag Introduced by Google in 2009, the canonical tag has rapidly become one
of our favorite SEO weapons. The canonical tag allows you to specify the primary
URL for a page on your site.
of our favorite SEO weapons. The canonical tag allows you to specify the primary
URL for a page on your site.
The tag looks like this:
<link rel=”canonical” href=”http://www.example.com
/primary-url.html” />
/primary-url.html” />
and goes in the <head> of a web page. Here’s how it works:
For any group of duplicate pages, you choose a single, primary URL. You add a
canonical tag to every one of the duplicates (including the primary page), specifying
the primary page.
For any group of duplicate pages, you choose a single, primary URL. You add a
canonical tag to every one of the duplicates (including the primary page), specifying
the primary page.
For example, if you have three duplicate pages named
/joe.html
/joseph.html
/joey.html
/joey.html
and you choose /joe.html as the primary URL, then all three of these
pages would get a canonical tag specifying /joe.html, something like this:
pages would get a canonical tag specifying /joe.html, something like this:
<link rel=”canonical” href=”http://www.example.com/joe.html” />
Search engines will read the canonical tag as a strong signal that all of your duplicate
pages should be consolidated in the search engine index, giving you a single, more
powerful page in the index rather than a bunch of weaker, diluted pages.
