Thursday 29 April 2010

Identifying canonical content

Search engines may down-rank pages if the same content is referenced by multiple URLs. This would apply in cases where URL parameters are added to the URL to put the page in different modes (e.g. sort order). It would also apply in the case of pages that are referenced by different portals (i.e. different domains).

For example the following URLs could all point to the same content:

  • http://<domain name here>/mypage.aspx
  • http://<domain name here>/mypage.aspx?sort=desc
  • http://<domain name here>/mypage.aspx?sort=desc&page=2
  • http://<another domain name here>/mypage.aspx

To assist search engines in identifying the canonical version of the content add a <link> tag to the <head> section of the duplicate content:

<link rel="canonical" href="http://<domain name here>/mypage.aspx" />

For Google’s guidance go here:

More on duplicate content:

Thursday 29 April 2010