7 Reasons Every e-Commerce Manager Should use the Rel Canonical Tag

In SEO, The Digital Marketing Blogby Kelvin5 Comments

We’ve had a few months now with new rel canonical tag from Google. We’ve carried out some experiments internally and have read the experiences other SEO’s. In that research it’s become apparent just what an SEO godsend it is for anyone working on an e-commerce site.

Is it the magic pill? Image Credit DraconianRain

You’ve probably already heard about the tag that helps you explain to search engines where you have duplication issues which you are aware of but don’t want to solve with a 301 redirect. What you might not have realised is just how versatile a tool it is.

We’ve got seven ways we thought it would be useful to anyone managing an online retail website but if you can think of any more do let us know in the comments.

Session IDs

We all know session IDs aren’t ideal from an SEO point of view, far too often the engines see domain.com and domain.com?sometracking as duplicate pages. An inexperienced SEO will just tell you to strip away that excess code, but they’ve clearly never dealt with the pragmatic reality of an e-commerce business before – It’s not always that simple.

You might have a legacy CMS which isn’t that flexible, or maybe someone more senior in the company wants the insight from the tracking so it doesn’t make sense politically to push the issue.

The most common reason we’ve encountered is that the site’s developers are so busy it may take months before they have the resource to deal with the problem. In this case, serving the rel canonical tag pointing at the definitive version of the page can be a quicker and easier solution. It is better from an SEO point of view than the current state.

Allow different sorting options

What’s one of the most common forms of duplication on an e-commerce site? Multiple sorting options creating duplicate pages of near identical content. It happens really often with Job Boards too.

The rel canonical tag will allow you to keep these from a usability point of view, and it is a lot less drastic than blocking the pages to search engines, which will nuke any valuable deep links these pages may have acquired over the years.

Products in multiple categories

If sorting options isn’t the most common duplication problem for ecommerce sites, it’s almost certainly when the same product page appears in different categories with different urls.

Clever information architecture can help, but there will always be occasions when usability concerns will result in the same product on two different URLs. The rel canonical tag solves a bunch of those problems.

But be consistent with where you handle the location of the canon page, as that’s the one which will appear in the SERPs, so needs all the usual onsite optimisation for rankings and to increase click-throughs.

Http vs. Https

Google are pretty good at knowing the difference between the secure version of your site and the not so secure, but are your users?

You may be lucky enough to be attracting natural links when your existing customers browse your site and link to pages of your site; but if they are linking to the duplicate https version of the site you won’t really see the benefit. A well placed rel canonical on every page of the https site can remedy that.

Print Versions

No follow and using the robots.txt file has solved many of the problems we used to see with duplication and print pages, but it can still cause the occasional slip-up. If you’ve gone to the effort of creating a print-friendly page it can’t be too much hassle to use the rel canonical just to be on the safe side.

SEO-Friendly affiliate links

Rob Kerry recently spoke about using rel canonical as a nice way to get SEO benefit from any inbound links from affiliates. I don’t think this has been used much as a tactic but it seems to make a lot of sense from my point of view.

Avoid your PPC Landing Pages Getting Indexed

I’ll admit this is a frequent problem but recently we had a client who for one reason or another had received a couple of nice, keyword-rich links from trusted sites to their PPC landing page. Because this page duplicated quite of lot of content from the main site, it was decided to block this page to the search engines. That seemed a waste of these highly trusted links. We could have changed the location of the PPC landing page and 301-ed the links but we were happy with the historical performance of that page, so wanted to leave things as they were. With the launch of the cross-domain rel canonical tag we had the perfect solution.

And if you happen to use Magento you don’t even need to worry about the implementation, Joost has already created a plugin to handle it.

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  1. Pingback: SearchCap: The Day In Search, January 8, 2010

  2. hi Kelvin

    Great article.

    I would also like to reinforce your information by saying that I have seen some great results from implementing the canonical URL element.

    After working on a number of Interspire shopping cart installations I was prompted to write a canonical url plug-in that has really helped clean up the search results on the sites using it.

    regards Dave

  3. Author

    What’s the details of the plugin Dave? I’ll add it to the body of the post?

  4. Sweet post! Probably one of the best on the canonical that I have seen.

    In my post:

    I talk about using the Canonical and how Bing does not support it. Wouldn’t you say to stick with a 301-redirect and the “noindex” until there total Search Engine support?

    Also, when you are dealing with a huge ecommerce site on different country code domains, what would you personally do for the products as they are identical over four-five sites. The canonical attribute seems like the ideal choice, but if Bing doesn’t recognize it, will your site be less visible through Bing?

    Love to hear your two cents.

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