Is your article too similar to another page? This free Duplicate Content Checker compares two texts or two URLs and shows what percentage of your article also appears in the other one, with every matching sentence highlighted. Leave the second box empty to get exact-match Google searches that reveal copies of your sentences online.
Frequently asked questions
How is the similarity worked out?
Both texts are split into overlapping five-word phrases. The score shows what share of the first text's phrases also appear in the second text, and each matching sentence is listed.
Can it check the whole internet for copies?
It compares the two texts or pages you give it. To look for copies online, use the Search on Google links it creates for your sentences, which run an exact-match Google search.
How much duplication is a problem?
Quotes and common phrases are normal. If more than about 30% of an article matches another page, rewrite it or point to the original with a canonical tag.
Is my text saved?
No. Pasted text is compared in your browser. URLs are fetched once to read their text and are not stored.
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How to use the Duplicate Content Checker
- Paste your article text, or a page URL, in the first box.
- Paste the text or URL you want to compare with in the second box.
- Click Check duplicate content and review the score and the matching sentences.
- Rewrite the highlighted sentences, or add a canonical tag pointing to the original.
When to use it
- Before publishing a guest post: make sure the article is not a copy of something already online.
- Checking writers and AI drafts: compare a draft with the source it was based on.
- Finding scraped copies: compare your page with a site that copied it.
- Fixing duplicate pages on your own site: two similar posts can compete with each other; merge them and redirect with our 301 Redirect Generator.
Want to sell or buy guest posts with original content? Browse our guest post marketplace.