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.

Do I need a canonical tag on every blog post and page?

Yes, it is a good idea to add a canonical tag to every indexable page, even if you think it has no duplicates.

A self-referencing canonical tells Google, “This exact URL is the main version.” That helps prevent issues from small URL changes like tracking links, category pages, or different URL versions.

Keep it consistent across your site. Use the full (absolute) URL and make sure it matches your preferred format, like https vs http and with or without a trailing slash.

After you update canonicals, you can speed things up by asking Google to recrawl the page using this guide on how to submit URL for indexing.

When should I use a canonical tag instead of a 301 redirect?

Use a canonical tag when you want multiple pages to stay live, but you want search engines to rank only one main version.

For example, you might keep a print page, a filtered product view, or a similar article version for users. The canonical tag tells Google which URL should get the SEO credit.

Use a 301 redirect when you do not want the old page to exist anymore. Redirects are best for moved pages, deleted pages with a replacement, or when you are cleaning up old URL structures.

If you are unsure, ask yourself: should visitors still be able to access both URLs? If yes, use canonical. If no, redirect.

Can I point a canonical tag to a page with different content?

No, you should only use canonical tags for pages that are identical or very similar.

If the pages are truly different, a canonical can confuse search engines and cause the wrong page to rank. It can also hide the page you actually want people to find.

If a page should not show up in search at all, consider a different option like a noindex tag instead. That tells search engines not to index the page, rather than choosing a “main” version.

When in doubt, compare the main text, intent, and target keyword. If they are not basically the same, do not canonicalize them together.

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

The biggest mistakes are using more than one canonical tag, creating canonical chains, or pointing to the wrong URL.

Only include one canonical tag per page. If you have two, Google may ignore both and pick its own version.

Avoid chains like A canonicals to B, and B canonicals to C. Point every duplicate page directly to the final main page you want indexed.

Also watch for small URL mismatches. Make sure the canonical uses the exact preferred version, like https, the correct domain, and the correct trailing slash style.

How can RightBlogger help me improve SEO around duplicate content and canonicals?

RightBlogger helps you spot and clean up SEO issues faster, which lowers the chance of duplicate content problems.

With SEO Reports, you can review on-page SEO signals across your content and catch problems that may hurt rankings. That makes it easier to keep your important pages clear and consistent.

A simple workflow is to publish, check your key pages for duplicated titles or similar posts, then confirm each page has the right canonical URL. This keeps your rankings focused on the page you actually want to win.

If you update canonicals or consolidate pages, recheck your internal links and request a recrawl so search engines pick up the changes sooner.