Canonicalization: SEO Best Practices

Canonicalization isn’t something new. In fact, it has been around since 2009. However, a lot of beginners in SEO still don’t get what the term actually is. Not to mention the best ways to use it to improve SEO. This page will show the ultimate guidance of canonical tags and how you can optimize your SEO by taking benefit of it.

Canonical URL: What Is It?

Photographer: Steve Johnson | Source: Unsplash

For short, it can be said that a canonical tag is an element of HTML mainly used to allow Google to know that there are two or more URLs that are duplicated, identical, or similar on a website. The canonical tag itself can be found in the webpage source. To find it there, you need to search for rel=”canonical”.

To understand more about canonical tags, you need to know that they have different names. They include a canonical link, rel canonical, canonical tag, and re=”canonical”. These terms are generally used by SEO practitioners to refer to the canonical URL.

Canonical Tag Vs Canonical URL

For SEO beginners, these two terms can be quite confusing. The canonical tag is used to refer to the main version of your web content. In other words, this is the URL that you intend to show up in the search results of Google. Meanwhile, a canonicalized URL is a website page equipped with a canonical tag. Not only that but it also comes with a different URL inside the canonical URL.

When you add a different URL to your website’s canonical tag, it means that instead of the URL page, you are asking Google to index the canonical tag. Once a website comes with a canonical link element that references another website, it can be said that this website has been successfully canonicalized. Keep in mind that canonicalization is the process to allow a preferred page version to be chosen over other versions.

Why Do You Need It for Your Page?

When it comes to duplicate content, you can be sure that it is a complicated subject. You need to know that there will be SEO problems if search engines are filled with a lot of URLs with similar content. This is where the canonicalization will be very beneficial for your website.

Canonical URLs can be self-referential. It means that it will be found on your page if URLs A, B, and C are duplicates. So, while URL A is a canonical version, there will be no problem if you put the tag pointing to A or URL A. Sounds obvious, isn’t it? However, it can be a common point of confusion, especially for SEO beginners.

Another reason why canonicalization matters is that it can help you avoid unforeseen problems. This is simply because the homepage usually duplicates, making it common to happen. Not only that but it also allows people to use many ways to link to your homepage. That will make it hard for you to control the practices. By including a canonical tag on your homepage, you can effectively prevent potential problems that come with homepage duplication.

How to Add Canonical Tags to Your Page

Photographer: Remotar Jobs | Source: Unsplash

Contrary to public belief, it is quite easy to implement canonicals. Here are the best ways you can do as a beginner business owner to add canonical tags to your website.

1.     Directly Implement Via HTML

This is one of the most common ways that people use to implement canonical URLs. You can do it simply by putting the attribute rel=”canonical” in a link element. You also need to place the absolute path of the version of the canonical tag within each URL.

If you want to implement canonical URLs in various duplicated pages, there will be an easy way you can do it. Just say, you have three identical pages – page X, page Y, and page Z. let’s pick page X as your preferred page.

Page X:

Page Y:

Page Z: https://example.coom/page-z

To add the canonical tags, you need to add the same <link rel=”canonical” href=”’/to Page X, Y, and Z.

2.     Setting Canonicals in Sitemaps

Another easy way you can implement canonical tags is by setting them in Sitemaps. You need to know that non-canonical pages in Google are not included in sitemaps. It means that only canonical URLs are listed there. This is because Google usually sees them as suggested canonicals. In this way, make sure that you don’t put non-canonical pages in a sitemap. If you want to use a sitemap, keep in mind that you specify only canonical URLs when you include them in there.

3.     Specify the Right Domain Protocol

This is a great way to implement canonical URLs if your website is on the HTTPS protocol. If this is your case, make sure that you properly reference it as your canonical tag. You need to know that it is a common mistake to make a reference to the incorrect protocol. In this way, you should check this properly before implementing the canonical URL to avoid issues in the future.

4.     Use Absolute URLs

Bear in mind that you should reference canonical URLs using absolute URLs instead of relative ones. This is aimed to make sure that these URLs will be interpreted properly.

Canonicalizing to Irrelevant URLs

So, what can you do to canonicalize irrelevant content? Well, the common practice is that you shouldn’t canonicalize your URLs if they are not near-identical or duplicate. Many SEOs out there are trying to pass link signals through canonical URLs from irrelevant content. They usually do it to improve their SEO ranking. However, this is not the way to use canonicalization. In this way, you should avoid canonicalizing unrelated content at all costs to avoid issues on your website in the future.


This is true that canonical tags are not mandatory when it comes to search engine requirements. However, given many unforeseen issues caused by URL duplication, canonical tags will help you avoid these problems. Not only that but it will be a great way to improve your SEO ranking.

Parker Casio Patty
Parker Casio Patty
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