Duplicate Sentence Finder
Find and highlight duplicate or similar sentences within any document.
Detect and Eliminate Duplicate Content for Better SEO
Duplicate content — whether within the same document or across multiple pages on your site — is harmful for both readability and SEO. Within a document, repeated sentences signal lazy writing and reduce the reader's trust. Across your site, Google penalises duplicate page content by not indexing multiple versions (only the "canonical" version ranks). Our tool catches intra-document duplicates and near-duplicates (paraphrased but highly similar sentences).
Frequently Asked Questions
Does duplicate content hurt SEO ranking? ▼
Yes — at the page level. Google does not penalise you in the traditional sense, but it will choose only one version of duplicate pages to index (the canonical). The non-canonical pages receive little to no organic traffic. Within a single document, duplicate sentences signal low quality and reduce the chance of the page being chosen for featured snippets.
What is the duplicate content threshold for Google? ▼
Google has not published a specific percentage threshold. In practice: 30% or more identical content between two pages starts to affect which URL Google chooses to rank. Below 15% is generally considered safe. Our tool's default 90% similarity threshold catches near-identical sentences; lower it to 70% to catch heavily paraphrased duplicates.
How to fix duplicate content issues on a website? ▼
For the same content on multiple URLs: (1) Add canonical tag () on duplicate pages pointing to the preferred URL, (2) Use 301 redirects from old URLs to new canonical URL, (3) Consolidate thin pages into one comprehensive page. For paginated content: use rel="next" and rel="prev" or noindex on paginated pages.
What is a self-referencing canonical tag? ▼
A self-referencing canonical tag is a placed on a page pointing to itself. This explicitly tells Google "this is the preferred version of this URL" — protecting against potential duplicate issues from URL parameters like ?sort=price or ?session_id=123.