How does Google handle the canonical tag?

Following on from our previous article “How does Bing manage redirects – 301s, 302s and the canonical tags?” Nick Roshon answers the question “How does Google handle the canonical tag?” Considering both search engines are supposed to treat the canonical tag the same there are some differences as Nick points out.

• As opposed to Bing, Google does not trust the site less if you mass use the canonical tag. In the video below Matt Cutts actually explains that featuring the tag on every page of your site will not harm your site.
• The other major point that Bing made was not to self-reference a canonical tag as there is no point. This contradicts what Google have said, as Nick points out, what Maile Ohye of Google says:“Yes, it’s absolutely okay to have a self-referential rel=”canonical”. It won’t harm the system and additionally, by including a self-reference you better ensure that your mirrors have a rel=”canonical” to you.”

This of course provides a mixed view but it looks like Google use the tag a little more intelligently and with the 90% of the UK market share belonging to Google there isn’t too much to fear if you follow their guidelines.