Duplicate Content & Text Similarity Checker
Compare two articles or documents side-by-side. Calculate exact N-gram Jaccard similarity percentage and highlight identical duplicate phrases.
Why Duplicate Content & Similarity Matters in SEO
Publishing two similar blog posts with 60%+ text overlap causes search engines to compete your own URLs against each other, diluting rankings and crawl budget.
If you syndicate press releases or guest posts across multiple domains, compare drafts to ensure each version has at least 30-40% unique value before publishing.
Our algorithm breaks texts into 3-word shingles and computes set intersections over set unions, providing mathematical similarity matching without remote server calls.
Frequently Asked Questions
No. This is a direct side-by-side text similarity and duplicate comparison tool. It analyzes the similarity between the two specific documents you paste, with 100% client-side privacy.
The tool uses a combined N-gram shingle Jaccard coefficient and longest matching phrase tokenization. It measures the overlap of unique 3-word and 5-word phrases relative to the total combined vocabulary of both documents.
Generally, content overlap exceeding 50% between two URLs on the same website may trigger internal duplicate content filtering by Google. For syndication, aiming for under 30% similarity is recommended.
No. All tokenization algorithms execute locally in your browser memory, allowing you to compare short paragraphs as well as 10,000+ word technical papers with zero network latency.