Duplicate Content and Canonical URLs

Due to the limitation of technical knowledge, many people are not aware of the existence of duplicate content on their website. Duplicate content is a no-no for Search Engine Optimisation.

Loss of ranking and traffic is a dire consequence to pay for a problem that can be quite easily fixed. The main issue with content duplication is that it will create confusion for Search Engines as to which page to include or exclude from their indices, which page should it gives the link value to and which one to rank for search terms. Thus it is highly recommended to write original content for your website and to ensure that none of the URL structure/metric create a duplicate content for your website.

What are the common causes of duplicate content?

Copying and pasting content from other website

Writing original content takes more effort and time, but the reward will be much greater.

URL parameters

Printer friendly version – It is not uncommon for printer-friendly-version web page to create duplicate page with the exact content on a different URL. For example: These two URL address (webfirm2015v2.webfirmdemo.com/print/ASX-announcement2011 and webfirm2015v2.webfirmdemo.com/ASX-announcement2011) has the exact same content but the other page is a printer-friendly-version but they will be treated as two separate pages by Search Engine and will be seen as duplicate page)

Session IDs – For an E-commerce website, usually each visitor is assigned session ID which is stored in the URL. For example: webfirm2015v2.webfirmdemo.com/about-us?SESSID=1234. In that URL the SESSID is a mark that a session ID is stored in the URL and it usually creates multiple version of the same page.

How to fix it?

301 redirect

The most effective way to counter content duplication is to set up a 301 redirect from the other page to the original page. As these pages are not competing with each other anymore, it will increase the chance for the original page to rank well in Search Engines.

As for how to set up a 301 redirect, it will be an entirely different post for some other time.

noindex, follow

A code that can be implemented in a certain page to tell the Search Engine’s bots to not include this page in their indices therefore it won’t rank for anything.


Another option is to utilize the rel tag of the HTML head of a web page. This tag will tell Search Engines bot to treat a given page as if it were a copy of another URL.

For example:

If you have this piece of code

<link href=”https://webfirm2015v2.webfirmdemo.com//blogs/” rel=”canonical” /) within the head tag of your HTML then you are telling Google or Bing to treat this URL (https://webfirm2015v2.webfirmdemo.com//blogs/what-is-title-tags) for example, as a copy of webfirm.com/blogs and to credit all the links and content value to that URL as well.

In summary, an awareness of duplicate content issue and ways to counter measure or prevent it is essential for your SEO campaign. Furthermore a couple of minutes of careful planning and writing an original content for your website will come a long way. Not only will you provide your visitors a highly relevant content, which may leads to increase your conversion rate, but it will also help with your ranking.

Image credit planeta on Flickr