Written by Fernando Maciá
“Canonical” is a linking element used to manage and remove duplicate content from a website. It is a suggestion to Google that tells it how we want our page to be indexed.
Sometimes, the canonical element can be used as a redirect, in the sense that Google can stop indexing a page in favor of indexing the one that is stipulated in its canonical, thus solving the problem of duplicate content.
However, the canonical, unlike a 301 redirect, does not transmit popularity juice to the destination URL.
We must also remember that the canonical element is only a directive for Google and not a command, so if it does not find the logic (for example, if it finds many internal or external links pointing to the canonicalized URL), it will not respect this directive and will continue to index the canonicalized URL instead of the canonical one.
When setting the canonical URL, it is recommended to define the absolute URL and not the relative URL.
For example, to set the canonical URL of the URL https://www.humanlevel.com/digital-marketing-dictionary/canonical-link-element:
- It would be correctly implemented:
<link href="https://www.humanlevel.com/digital-marketing-dictionary/canonical-link-element" rel="canonical“>
- It would be incorrectly implemented:
<link href="/digital-marketing-dictionary/canonical-link-element" rel="canonical">
There are many cases where we should use the “canonical” link element.
Duplicate product sheets
For example, if an online store does not have an optimized architecture, it is very likely that we will find duplicate product sheets simply because we included them in different sections at the time:
- Pilates ball ‘pro41X’ in the ‘Balls’ section: https://deporteatope.com/pelotas/balonpro41X.html
- Pilates ball ‘pro41X’ in the ‘Pilates’ section: https://deporteatope.com/pilates/balonpro41X.html
In these cases, Google would be indexing two different URLs with the same content, something it does not like at all. Just stop and think about one of its most updated and feared algorithms: Panda, which is dedicated to penalize and lower in the rankings to those websites that have a high rate of duplicate content on site.
Another example would be the different product presentations that can lead to parameterized URLs that filter product features. For example, if our pro41X ball had different colors and sizes, we could find URLs like these, where the only thing that would change would be the photo or the measurements:
- Pilates ball ‘pro41X’ yellow: https://fullsport.com/balls/pro41Xball.html?color=yellow
- Pilates ball ‘pro41X’ XL https://fullsport.com/balls/pro41Xball.html?talla=xl
For Google, these URLs could be catalogued as duplicate content, so our recommendation would be to establish in the
<head> the following canonical in each one of them:
<link href="https://fullsport.com/balls/pro41Xball.html" rel="canonical">
Parameterized URLs are also those we create to track campaigns or those with AdWords tagging. That is, they have the parameters “?utm_” or “?gclid”.
For example: https://www.humanlevel.com/en/blog-en/online-advertising/new-graphic-reports-on-google-adwords.html?utm_source=facebook&utm_medium=redessociales&utm_content=antoni&utm_campaign=articulos
In the first link of the references section you will find different uses of the canonical link element.