Canonical URL

Did you know the same post on your site can open at several different addresses? A canonical URL is the one main address you want search engines to treat as the original.

It matters because duplicate versions of a page can split your ranking signals. A canonical tag tells Google and other search engines which version should get the credit.

What is a canonical URL in WordPress?

It is set with a small tag inside the <head> section of your page. Here is how it looks:

<link rel="canonical" href="https://example.com/sample-post/" />

Think of it as signing the original copy of a document. Other copies may exist, but everyone knows which one is the real one.

Why do duplicate URLs happen?

Here are a few common reasons:

• Tracking codes added to links, such as ?utm_source=newsletter.
• Both the HTTP and HTTPS versions, or the www and non-www versions, still loading.
• A post that you republished on another website.

Without a clear signal, search engines have to guess which version to show, and they don't always guess right.

How WordPress handles canonical tags

By default, WordPress adds a canonical tag to every single post and page, pointing to its own permalink. SEO plugins take this further. They usually add canonical tags to archive pages too, and they let you set a custom one for any post.

1. First, open the post in the editor.
2. Next, find your SEO plugin's panel and open its Advanced section.
3. Now, paste the preferred address into the Canonical URL field.
4. Finally, save the post.

To check the canonical tag of any page, open it in your browser, view the page source and search for the word canonical. Not sure which plugin to use? Have a look at our list of the best WordPress plugins and tools for SEO.

That's the whole idea behind canonical URLs: one piece of content, one main address. Share your questions in the comment box below.