Canonical Tag: What is it and why it matters

Last Updated April 22, 2024

Today, we are going to talk about a term that is crucial for your blog’s SEO – the Canonical Tag.

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What is a Canonical Tag?

A canonical tag, also known as rel=canonical, is a piece of HTML code that helps search engines identify the main version of a page when there are multiple pages with identical or very similar content.

In simpler terms, it’s a way to tell search engines, “Hey, this is the main version of this page that I want you to index and show in the search results.”

For example, the canonical tag for your main blog page might look like this:

<link rel="canonical" href="https://yourblog.com/main-page/" />

Why Are Canonical Tags Important?

Avoid Duplicate Content: Search engines, like Google, don’t like duplicate content. It confuses them, and they might end up indexing and ranking the wrong version of your page. Canonical tags help you specify which version of the page you want to be considered as the main one.
Consolidate Link Equity: If there are multiple versions of a page, the backlinks to those pages will be divided among them. By using a canonical tag, you consolidate the link equity to the main page, which can help improve its ranking.
Improve Crawling Efficiency: Search engines have a crawl budget, which is the number of pages they will crawl on your site in a given time. By using canonical tags, you can help search engines to not waste their crawl budget on duplicate pages.

Best Practices for Using Canonical Tags

Use Absolute URLs: Always use the absolute URL in the canonical tag, not the relative URL. For example, use https://yourblog.com/main-page/ instead of /main-page/.
Self-Canonicalize: Even if a page doesn’t have any duplicates, it’s still a good practice to include a self-referencing canonical tag. This helps to avoid any confusion for search engines.
Be Consistent: Make sure that the URL used in the canonical tag is consistent across the site. For example, if your site uses https, make sure that the canonical tag also uses https.

Common Mistakes to Avoid

Canonical Chains: A canonical chain occurs when Page A references Page B as the canonical, and Page B references Page C as the canonical. Always point the canonical tag directly to the main version of the page.
Multiple Canonical Tags: There should only be one canonical tag on a page. If there are multiple canonical tags, search engines might ignore them.
Non-Similar Content: Don’t use the canonical tag on pages with completely different content. It should only be used on pages with identical or very similar content.

Conclusion

Canonical tags are an essential tool for bloggers to manage duplicate content, consolidate link equity, and improve crawling efficiency. By using them correctly, you can help search engines understand your content better and improve your blog’s SEO.

When should I use a canonical tag on my blog?

A canonical tag is used when you have two or more pages with the same, or almost the same, content and you want search engines to rank one main version.

This often happens with URL variations, like tracking parameters, print versions, or the same post showing up under different category pages. It can also happen when you republish a post and the old URL still exists.

Adding a canonical tag helps Google understand which page is the “official” one. That way, your main page is more likely to show in search results, and you avoid splitting SEO value across duplicates.

As a quick check, look for pages that read the same but have different URLs. If the content is truly different, do not use canonical and consider other options like a separate page or a redirect instead.

Should every page have a self-referencing canonical tag?

Yes, it is usually a good idea for each page to include a canonical tag pointing to itself. This is called self-canonicalizing.

It helps prevent confusion if your content gets copied, if your site creates multiple URL versions, or if someone links to a messy version of your URL. Search engines then have a clear “main URL” to follow.

Make sure the canonical uses the full, absolute URL, like https://yourblog.com/post/ instead of /post/. Also keep it consistent with your preferred version, like HTTPS, and the same trailing slash style.

If you are not sure whether Google has indexed the right version yet, you can also follow a process to submit a URL to Google for indexing after your canonicals are cleaned up.

What is the difference between a canonical tag, a 301 redirect, and a noindex tag?

A canonical tag tells search engines which version of similar pages should be treated as the main one. It keeps both pages accessible to visitors, but guides Google toward the page you want ranked.

A 301 redirect sends people and search engines from one URL to another URL. Use a redirect when the old page should not be visited anymore, like when you permanently changed a URL.

A noindex tag tells search engines not to index a page at all. It is useful for pages you do not want in search results, but still want available to readers, like some thin or private pages. You can learn more in the RightBlogger noindex tag glossary.

In simple terms: canonical is “rank this one,” redirect is “go here instead,” and noindex is “do not show this in search.” Choose based on what you want users and Google to do.

What are the most common canonical tag mistakes, and how do I fix them?

The most common mistakes are using more than one canonical tag, creating canonical chains, or pointing to the wrong page. Any of these can cause Google to ignore your signals.

A canonical chain is when Page A points to Page B, and Page B points to Page C. Fix it by pointing every duplicate page directly to the final main page you want indexed.

Also make sure you are only canonizing pages that are truly similar. If two pages have different intent or different main content, they should not share the same canonical.

Finally, keep your URLs consistent, especially HTTP vs HTTPS and www vs non-www. Mixed signals can waste crawl time, so it also helps to keep your site organized with tools like a clean XML sitemap.

How can RightBlogger help me improve SEO when dealing with duplicates and canonical tags?

RightBlogger can help you spot and improve SEO issues faster, so you spend less time guessing and more time publishing. While canonical tags are usually set in your site theme or SEO plugin, your content and internal setup still play a big role in avoiding duplicate problems.

For example, RightBlogger can help you create clearer, more unique content so similar posts do not compete with each other. It can also help you refresh older posts so the “main” version is truly the best version.

A practical workflow is to review your pages for overlap, then prioritize fixes on posts that matter most for traffic. After that, use RightBlogger SEO Reports to catch on-page issues that can hold rankings back.

If you update content often, you can also streamline improvements with Auto Optimize for SEO. Keeping your content strong makes your canonical choices easier and more effective.