What Is Canonical Tag?
A canonical tag is a short line of HTML code that tells search engines which page is the main version when you have similar or duplicate pages. It helps Google and other search engines know which URL to show in search results.
Definition
A canonical tag is an HTML <link> element placed inside the <head> of a web page. It uses the attribute rel='canonical' to point to the preferred URL that should be treated as the main page.
Simple meaning. A canonical tag says. This is the original page. Please treat this URL as the main source.
Why Canonical Tag Matters
- Prevents duplicate content issues by telling search engines which version of a page to trust.
- Combines ranking signals such as links and user data into one main URL instead of splitting power across many similar URLs.
- Improves crawl efficiency so search engines spend less time on duplicates and more time on your important pages.
- Gives cleaner search results so users see the best version of your page, not many confusing copies.
How Canonical Tag Works
When a search engine bot visits a page, it reads the HTML code in the <head> section. If it finds a canonical tag, it uses the URL in that tag as the main version.
Basic example inside the page head.
<link rel='canonical' href='https://www.example.com/product' />This tells search engines.
- The preferred URL is
https://www.example.com/product. - Other similar URLs should be treated as copies of this main page.
Search engines then focus ranking signals on that canonical URL, which usually helps that page perform better in search results.
Example of Canonical Tag
Imagine you have one product, but it can be seen with different URLs.
https://www.shop.com/shoes?color=redhttps://www.shop.com/shoes?color=bluehttps://www.shop.com/shoes
All these pages show the same main shoe, only the color filter changes. To keep search engines from seeing them as separate pages, you can choose one main URL and add a canonical tag on every version.
<link rel='canonical' href='https://www.shop.com/shoes' />Now search engines understand that /shoes is the master page for this product, and the filter pages are just alternate views.
FAQs
Where do I put a canonical tag?
Place the canonical tag inside the <head> section of your HTML. It should appear once per page and point to the chosen main URL.
Can a page point a canonical tag to itself?
Yes. This is called a self referencing canonical. It is common and helps confirm to search engines that this URL is the main version of that content.
Does a canonical tag fix copied content from other sites?
No. A canonical tag only controls versions inside your own site. It does not stop other websites from copying your content or solve plagiarism by itself.
Is a canonical tag the same as a redirect?
No. A redirect moves users and bots to a new URL. A canonical tag only gives a suggestion to search engines about which URL is preferred. Users stay on the page they visited.
