April 23, 2013 by stevenmacdonald
Rel=canonical, the HTML markup that specifies duplicate content exists on a website and rel=next/ re=prev, the HTML markup that helps Google index pages that occur in a series of paginated content are commonly misunderstood in the world of online marketing and e-commerce. Whether canonicalizing your entire site to one page or incorrectly implementing both rel=canonical and rel=next/ re=prev in your e-commerce store can lead to fewer pages being indexed by search engines. These issues have become so popular they even prompted Google to publish a blog post on rel=canonical mistakes – With incorrect implementation of rel=canonical and paginated content listed as the number one used mistake.
Before we dive into research I’ve made on e-commerce stores, let’s look at what both rel=canonical and pagination are and how they can affect your website.
What is rel=canonical?
By using rel=canonical on your website, you are informing Google you have a set of pages with similar content (or duplicate content) and would like to display a specific page.
On an e-commerce store, it’s common to have several pages with the same content due to different entry points. For example, you might use the search function to find a product or sort products by rating. This can lead to one pagehaving two (or more) URLs:
If you are not using rel=canonical, Google will choose which page to index in the search results based on the search. By implementing rel=canonical you can tell Google which page they should display.
In the above example, let’s say we want to only index the /ratings/ url. We would implement the following on the /search/ page in the header:
- <link rel=”canonical” href=”www.example.com/ratings/category/products/product-1A” />
By doing so, you are telling Google to index /ratings/ so when a search is performed, the page will appear in the search results.
What is pagination?
In September 2011, Google announced ways to handle pagination by using rel=“next” and rel=“prev”.
Pagination can occur on different types of websites, including:
- Blog platforms
- News/ media sites
- E-commerce stores
The issue Google has is which page to show in the search results. The best solution is to include a View All page instead of having a series of pages as Google prefers View All pages, which results in “a better user experience” (as shown below):
If a View All page is not possible, then you can implement rel=”next” and rel=”prev” on your site to inform Google about the series of pages. Let’s take a look at a series of pages that could suffer from pagination:
In order to avoid any potential issues, you should implement rel=”next” and rel=”prev” on the pages as follows:
On the main page, www.example.com/product-type, you’d include in the <head> section:
- <link rel=”next” href=”www.example.com/product-type?page2″ />
On the second page www.example.com/product-type?page2 , you would include in the <head> section:
- <link rel=”next” href=”www.example.com/product-type?page3″ />
- <link rel=”prev” href=”www.example.com/product-type” />
On the third page, www.example.com/product-type?page3, you would include in the <head> section:
- <link rel=”prev” href=”www.example.com/product-type?page2″ />
A few points when implementing the code:
- The first page only contains rel=”next” and no rel=”prev” markup.
- Pages two to the second-to-last page should be linked with both rel=”next” and rel=”prev” markup.
- The last page only contains markup for rel=”prev”, not rel=”next”.
- rel=”next” and rel=”prev” only need to be declared within the <head> section, not within the document <body>.
Research on e-commerce stores
During the last six months, I have been working with e-commerce stores based in Scandinavia. A lot of time has been focused on the search index and getting websites with thousands of pages to rank.
This research has lead me to find a lot of articles on rel=canonical and pagination In most cases, the rel=canonical tag is pointing to page one in the series. In the following example, we will use: http://www.example.com/products/brand.
To see the canonical page, you can view source code of the page and search for “rel=canonical”.
What I have found is that in many cases the rel=canonical implemented in the series of pages all point back to page one in the series; this means:
All point back to http://www.example.com/products/brand/
By doing so, these series of pages are not being indexed by Google. If this were a real website, you could use Google’s search operator ‘site to show this behavior (replace the example site below with your own series of pages):
There is also a great article from Search Engine Land that caused a full length video (16 minute) to be created by the search team at Google; Pagination and SEO.
“No Place For Rel=Canonical”
The “The Really Complicated Technical SEO Infrastructure Issues” panel at SMX Advanced started with controversy when REI’s Jonathan Colman said that REI.com benefited from using rel=canonical on the product pages of its catalog. For example, if there were 10 pages of tent products, pages 2 through 10 all implemented a canonical tag which pointed back to page 1. This is when Google’s Maile Ohye, who was also on the panel, piped up and said that this was not a proper implementation of the canonical tag. So ideally, do not use this approach. ”
In order to implement both rel=canonical and rel=’next’/ rel=’prev’ correctly, keep it simple by:
- Only use rel=canonical for pages with similar or duplicate content
- If you have a series of pages, only use rel=’next’ and rel=’prev’.
If your organic traffic has decreased since implementing rel=canonical and rel=next/ rel=prev, you should check both your web analytics and series of pages on your website immediately. By cleaning this up site-wide, you will see an improvement in organic traffic as more pages become indexed by Google.
Have you found any issues when implementing rel=canonical on your e-commerce store? By addressing the above, have you noticed an improvement in your organic traffic? Feel free to comment below.
About Steven: Steven Macdonald has been working with online marketing since 2005. Experienced in online gaming and travel, Steven is currently working on global SEO with SuperOffice CRM and regularly contributes to the Tribes blog.