What is Duplicate Content?
Technical SEO
Duplicate content means identical or substantially similar content appearing at multiple URLs, either on your site or across different sites. Search engines struggle to determine which version to index and rank, diluting your SEO potential.
This isn't about plagiarism or penalties. Google rarely penalizes duplicate content unless it's manipulative. The problem is that multiple pages competing for the same keywords split ranking signals, weakening all versions.
Why duplicate content matters
When you have duplicate content, search engines must choose which version to show in search results. They might pick the wrong one, or rank all versions poorly because signals are split between them.
Backlinks, link juice, and user engagement get divided across duplicate URLs instead of consolidating behind one authoritative page. This is essentially keyword cannibalization at the content level.
Common causes
Multiple versions of your homepage (www vs non-www, http vs https) create duplicate content if not properly configured. URL parameters like ?sort=date or ?page=1 can generate duplicate versions of the same page.
Syndicating your content to other sites without proper attribution can create duplicates. Printing-friendly versions of pages or mobile-specific URLs might duplicate your main content.
How to fix duplicate content
Use canonical URLs to tell search engines which version is the main one. Add a canonical tag pointing to your preferred URL on any duplicate pages.
Set up 301 redirects to consolidate multiple URLs into one. If you have both www and non-www versions, redirect one to the other permanently.
For syndicated content, add a canonical tag pointing back to your original post. This tells search engines where the content originated and which version should rank.
Related Terms
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