Canonical tag
A canonical tag is a line of HTML that tells search engines which version of a page is the original. It prevents duplicate content from competing for the same ranking.
Also known as:
rel=canonical, canonical URL, canonical link
What is canonical tag?
A canonical tag is an HTML link element placed in the page head that points to the preferred version of a page when multiple URLs serve identical or near-identical content. The tag looks like <link rel="canonical" href="https://example.com/page" /> and it tells Google which copy to index, rank and consolidate signals around. Without canonicals, an online store with 500 product pages reachable through filters and tracking parameters might have 5,000 indexable URLs competing against each other.
The problem: brivvy.io/pricing, brivvy.io/pricing?ref=email and brivvy.io/pricing/ all show the same content
The fix: Each variant carries
<link rel="canonical" href="https://brivvy.io/pricing" />The effect: Google treats all three as one page and ranks the canonical URL only
Why does canonical tag matter?
Duplicate content is one of the quietest, most common drains on a site's organic performance. When 10 URLs serve the same content, search engines split the ranking signals between them and pick one to display, which may not be the version you want. Canonical tags tell Google exactly which page to count, which is especially important for ecommerce, multilingual sites and any setup with URL parameters.
How do you use canonical tag?
Add a self-referencing canonical to every important page, even when no duplicates exist, so future parameter or pagination changes do not cause issues.
Point parameter-stripped, paginated and filtered versions of a page at the clean canonical URL of the original.
Audit your canonical setup quarterly with a crawler like Screaming Frog or Sitebulb, since misconfigured canonicals can wipe a page out of the index.
