Set a global canonical tag to improve SEO

When there are multiple versions of a page with duplicate content, canonical tags (also known as rel="canonical" tags) tell search engines which webpage is the primary or preferred version to display in search results. You can set a global canonical tag to automagically create canonical tags for every page on your site.

In this lesson, you’ll learn:

1. What are canonical tags?
2. How to set a global canonical tag

What are canonical tags?

Canonical tags tell search engines that a specific URL represents the primary or preferred version of a webpage so they don’t interpret different versions of the page as duplicate content. For example, search engines may perceive the following as duplicate content:

• URL variations (e.g., http vs. https, www vs. the root domain)
• URLs with parameters applied for filtering and sorting (e.g., https://university.webflow.com/docs vs. https://university.webflow.com/docs?topics=seo)
• multiple versions of a page that share a common language but differ in dialect (e.g., a page with an Australian English version and a Canadian English version)

Duplicate content can cause SEO penalties and “keyword cannibalization,” where multiple pages on a site compete for the same keywords and harm each other’s rankings in the process. Canonical tags prevent these issues by directing search engines to the intended version of your content you want to appear in search results. They also consolidate ranking signals (e.g., backlinks) to the preferred version, which concentrates SEO efforts on a single URL and increases its chances of ranking higher in search results.

How to set a global canonical tag

When you set your site’s base URL (e.g., https://www.yourdomain.com) as the global canonical tag, that URL is combined with each page’s unique slug to populate canonical tags for every page on your site.

The global canonical tag URL should match your site’s default domain. However, if you’re managing duplicate content across multiple domains or subdomains (e.g., using a reverse proxy setup), you may need to set a different canonical URL.

Important: You must include the HTTP/HTTPS protocol in your global canonical tag, as search engines may interpret variations as duplicate content (e.g., https://yourdomain.com is different from http://yourdomain.com). If your site’s default domain is set to the www subdomain, you must also include the www URL prefix in your global canonical tag (e.g., https://www.yourdomain.com). You must exclude the trailing slash at the end of your URL — otherwise, the canonical URLs for all of your site’s subpages will include double slashes (e.g., //contact).

To set a global canonical tag:

1. Go to Site settings > SEO > Global canonical tag URL
2. Add your site’s base URL (e.g., https://www.yourdomain.com)
3. Save your changes

You’ll need to publish your site for the changes to take effect.

Note: If you inject your site’s canonical tag through another tool (e.g., Google Tag Manager), you shouldn’t set a global canonical tag in Webflow. This will create multiple canonical tags on your pages, which search engines may ignore entirely.

Pro tip: Ask Google to recrawl your site after setting a global canonical tag to ensure search results are updated as quickly as possible.