The canonical tag is placed in the source code of your web page to indicate to search engines a "canonical" URL in a set of pages with identical content. Here's what you need to know about this canonical tag, and how to set it up.
Avoid duplicate content by telling search engines which page is the original? This is what the canonical tag does.
Search engines hate plagiarism… even when it concerns the same website! Duplicate content on several pages within your own website could lead to penalties: poor positioning, or worse, a complete absence of all the pages concerned in the engine results! To avoid this, there is fortunately a very simple solution: the canonical tag.
Canonical tag: but what are we talking about, exactly?
Behind this strange canonical tag name hides a simple html tag, just like the Hn titles or the meta description. But this one has a very particular reason for being: it tells search engine robots that your web page is the only one, the only one... In short, that it is indeed the canonical URL to be considered in a set of pages. This, in case one or more other identical page(s) exist on your site.
In short, the canonical tag is like a signpost aimed at avoiding the consequences (harmful for your website) of duplicate content. It points to the default version of a set of pages that are too similar, or even completely identical, created voluntarily or by mistake (for example during a URL modification).
Avoid duplicate content thanks to the canonical URL
Duplicate content, that is to say the multiplication of identical or almost identical content, is not much appreciated by Google. Even if these contents are all hosted on the same website, they risk creating confusion among crawler robots, which then no longer know which Saint to turn to.
The canonical tag helps them find their way around easily. The canonical URL points the finger at the pages taken into account in the search results, at the expense of the others whose content is too close. For example, if your site contains several versions of the same page (created over updates), you designate which one should be retained by search engine robots, and displayed in the SERPs. The others will simply be ignored.
The benefits of this precious canonical beacon
In fact, the canonical tag allows you to:
- Exclude web pages whose content is close to the canonical URL;
- to focus on a single URL the various incoming links (as part of your netlinking) to increase its popularity;
- to circumvent the risk of penalties that could fall on you if too many contents are duplicated at the same time on your website.
How to insert a link rel=canonical tag on a web page?
To report your favorite pages, simply place the canonical tag in the <head> area of the source code of the desired page. It should look like this:
<head>
<link rel=”canonical” href=”http://examplepage.fr/originalpage.html” />
</head>
You can further boost the effect of the canonical tag by using a sitemap file to indicate the URLs to index.
Warning: place only one tag of this type in the same page! Otherwise, the robots will pass without seeing them…
