It’s not unusual for a website to have similar or identical content intentionally across multiple URLs. However, without proper consideration, this can have a negative effect on your SEO efforts.
Canonical URLs and tags help solve this problem. This is because they tell search engines which version of a page should be considered the primary one. With this in mind, let's explore what canonical tags are, why they matter, and how to implement them effectively.
A canonical tag (also known as "rel=canonical") is a HTML element that tells search engines which version of a URL (the canonical URL) should be treated as the master copy.
Essentially it tells Google that this is the original version of the page, and any other similar pages should be considered intentional duplicates.
The canonical tag will look like this:
<link rel=”canonical” href=”https://www.example.com/original-page”/>
Canonical tags should be used to handle duplicate content and inform the search engine which page should be indexed. The pages that you want to be indexed need to include a self-referential canonical tag.
However, it’s important to note that canonical tags are hints rather than directives, so Google may not always recognise your tags.
Duplicate content is a common issue. It’s often seen when there are:
Duplicate content can also occur across regions and languages. Content indication across regions and languages should be managed using hreflang tags to give Google an indication of what content to serve in what country or language. But, pages that are managed with hreflang should still have a canonical system in place.
Without canonical tags, search engines might:
Canonical tags should be placed in the <head> section of your HTML. However, it’s rare that you’ll ever need to manually add the tag to your code, since most modern content management systems provide straightforward support for canonical tags, with either built in functionality or plugins.
When implementing canonical tags, keep these five things in mind:
Always include a canonical tag on every page, even if it points to itself. This prevents others from canonicalising your content to their sites and ensures consistent implementation across your site.
Always use complete URLs in canonical tags rather than relative paths. So instead of "/blog-post", you’d use "https://www.example.com/blog-post". This eliminates any ambiguity for search engines.
Choose one version of your domain (www or non-www) and stick to it. The same applies to HTTP vs. HTTPS. Your canonical URLs should consistently use your preferred versions.
For paginated content (content split across multiple pages), either point your canonical to the first page or, preferably, use a view-all page as the canonical version if one exists.
If you’re managing multiple domains use cross-domain canonical tags to indicate the original source. This helps preserve SEO value and prevents duplicate content issues across different websites.
It’s easy to make mistakes with canonical tags, so ensure you avoid these common errors:
You can use Google Search Console to understand what the search engine is indexing and why. Simply click ‘Indexing’ in the menu on the left and choose ‘Pages’. In here you will find information about your indexed and non indexed pages. We also recommend keeping an eye on your chosen rank tracker to ensure the right pages are being selected
You can also use the URL inspection tool. Simply type in the URL you want to check and in the ‘Page indexing’ section, click the drop down. There is a section called ‘Indexing’ that will show whether Google has respected the given canonical or chosen their own.
If you haven’t already set up Google Search Console for your domain, we highly advise you do so as it provides valuable insights about your web pages.
Alternatively, you can crawl your website using a tool such as Screaming Frog. In the canonical section you can review indexed pages and see what URLs should and shouldn’t be there due to canonicals in place.
By following best practices and avoiding common mistakes, you can effectively use canonical tags to manage duplicate content issues and improve your website’s SEO performance.
Remember to regularly audit your canonical implementation and adjust as needed based on your site's evolving structure and content strategy.
If you want expert help implementing canonical tags or managing duplicate content, get in touch with the experts today.
