Canonical URLs and robots meta
Control crawling and avoid duplicate content with meta tags.
Duplicate Content Problem
Search engines may encounter your page at multiple URLs:
http://example.com/pagehttps://example.com/pagehttps://www.example.com/pagehttps://example.com/page/(trailing slash)https://example.com/page?utm_source=newsletter
Google must decide which URL to index — and may penalize for duplicate content.
The canonical Link Tag
Tell search engines the preferred URL with rel="canonical":
<head>
<!-- This is the canonical URL for this content: -->
<link rel="canonical" href="https://example.com/blog/html5-guide">
</head>
<!-- No matter which URL the page is accessed from,
this tag signals to Google which URL to index -->
<!-- Link equity is consolidated at the canonical URL -->All lessons in this course
- title and its Role in SEO
- meta charset viewport author and description
- Canonical URLs and robots meta
- Favicon and Apple Touch Icon