Zencart canonical link – will it really help?

Google has announced the use of canonical link tag not too long ago, and other search engines also follow this move. Some of you might have never heard about this term before so I will give you a very brief definition here:

Because of the use of dynamic urls, one single web page can have more than 1 valid urls (address) pointing to it. Google as well as other search engines will more than likely pick of these links as official link and the others are flagged as duplicated content. The problem is that we are not sure which link will be picked. The canonical tag allows you to do just that: to tell THE LINK you want to use as the official one.

There is a recent post on Google’s blog discussing this issue which I strongly encourage you to read!

As Zencart DOES create various links for the same page, for example a product info link can be:

  1. http://yoursite.com/index.php?main_page=product_info&products_id=19
  2. http://yoursite.com/index.php?main_page=product_info&cPath=12&products_id=19
  3. http://yoursite.com/index.php?main_page=product_info&cPath=14&products_id=19

(Those are just 3 main variants: the first is a link without category path, the second is the correct link while the 3rd one is the link for linked product)

So to answer the question presented in this post title: Yes Canonical link will help your cart ONLY IF YOU USE IT CORRECTLY. Some Zen-cart developers have offered ways to take advantage of this new tag. For example, you can check 1 proposed solution at jasonjgreen.com/blog

Before you rush to your ftp client to apply the new code, I have a big warning for you: the code suggested there should NOT be used, in my opinion.

  1. If you are not using any SEO Url Module for Zencart, the code above which strips all the query strings will make it so that all the links on your site have the same canonical link.
  2. Even if you do use SEO Url Module, our Simple Seo Url mod for example may create an all product listing page like this: http://yoursite.com/products_all?page=X where X is a page number. Obviously page 2 will have different content with page 9, if the code above is used then these pages will have the same canonical link (which makes no sense)

Before we go any further, I will remind you that if you are using Simple Seo Url module published by us the 1st and 2nd issues are automatically solved for you (hey, and if you don’t have linked products on your site you are good to go). The 3rd one is currently still an issue though (same product but more than 1 link if it belongs to more than 1 category). The reason why we have not supported canonical link in SSU functions yet is because it is something that is so dangerous and can be potentially dangerous if applied wrongly.

I have several options in mind, one of which is to present canonical link in case that SSU can be 100% sure of the correct canonical link (for example, only present canonical link in product info page to fix the problem with linked products). If you have any suggestion, please let us know!


  1. Using canonical link tag on Zencart | eCommerce and Marketing News & Tips says:

    [...] a few days ago I posted an article about canonical link tag and how it helps your zencart stores, in that article I also warned about certain misunderstandings regarding how canonical link tag [...]

  2. Natalie says:

    This is a very interesting issue. In the perfect world, I would like to have full control of my canonical links. I think it would be nice if there is a way to generate xml file with all content that can be considered duplicate by Google and then manually edit by marking the preferred URLs to be canonical.

  3. admin says:

    I myself prefer to assign the canonical url that I’m absolutely sure about and the leave the others unset as Google advised. The idea to build an xml file is nice but there a lots to be solved:
    1. How do you group these links? Which links should fall under the same canonical url?
    2. What about links generated by 3rd party modules etc?
    3. Do the normal store owners have the knowledge and time to set all these?

  4. Kris Sookma says:

    I agree, Right now I am going to search online about how to signify canonical on only my product pages. I dont want a canonical on my other pages.

    Before reading this I was unsure as to if the 2nd 3rd 4th pages etc. of the category pages were being seen by google but after reading this it seems that yes google does see those pages even with the dynamic characters…

  5. ksblog says:

    I just learned that Zen Cart support Canonical from v1.39
    You can see how to set it up in here: http://ksblog.org/index.php?q=zen-cart-seo-canonical-tag-support.
    It’s quite easy.
    It would be perfect if you turn on the SEO friend URL and work with Canonical tag.


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