Posts Tagged ‘tag’

Canonical URL Tag

Friday, February 13th, 2009

Today, it was announced the Google, Yahoo and Live will all be supporting a new canonical URL tag.  The tag is a simple solution that will help resolve a host of canonical URL issues.  Put simply, a canonical URL is the authoritative or correct version of a URL when several options exist.

If several versions of a page are indexed by Google, it may trigger a duplicate content filter, causing valuable pages to be dropped from the index.  A common example of this is when a site’s index page is mistakenly seen as two separate pages with the URLs such as “http://www.example.com” and http://example.com”. Canonicalisation can also be problematic for e-commerce sites as session ids can also trigger the problem.

The new tag is very simple and should be placed in the head section of your code as follows:

<link rel=?canonical? href=?http:www.example.com/example? />

This will indicate the correct format of the URL to be indexed and ensure that all links to the page are consolidated to the single URL.