A canonical URL is the preferred version of a webpage that helps prevent duplicate content issues in SEO. It tells search engines which URL to index when multiple versions of a page exist.
For example, these URLs might lead to the same page:
✅ example.com/product
✅ example.com/product?ref=123
✅ www.example.com/product
A canonical tag (rel="canonical") in the HTML <head> tells Google which version is the primary one.
Do You Need a Canonical URL?
Yes, if:
✔ Your site has duplicate or similar content across multiple URLs.
✔ You use UTM parameters for tracking but want one URL indexed.
✔ Your store has pagination issues in an ecommerce setup.
✔ You want to consolidate SEO signals to a single URL instead of splitting ranking power.
Final Thought
Canonical URLs improve SEO by preventing duplicate content penalties and ensuring search engines focus on the right page. If your site has multiple similar URLs, implement canonical tags to maintain ranking consistency.