What is this Tool?
The Plagiarism Checker compares two pieces of text and calculates a similarity score based on matching sentences and phrases. It highlights which parts of your text overlap with the source, making it easy to identify copied content. This tool works entirely in your browser — no text is ever uploaded to any server, making it completely private and secure.
This is a document-to-document comparison tool. It is ideal for checking if a student's submission matches a reference document, comparing a paraphrased version against the original, or verifying that rewritten content is sufficiently different from the source material.
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Frequently Asked Questions
How do I check plagiarism between two documents?
Paste the original document in the left box and the text you want to check in the right box, then click Check Similarity. The tool instantly shows a similarity percentage, highlights matching sentences and lists common phrases. No file upload needed — just paste the text directly.
Can I compare two documents for plagiarism for free?
Yes — this free plagiarism checker lets you compare two documents or texts side by side with no signup, no upload and no cost. Paste both texts and get an instant similarity score and matched sentences. It works entirely in your browser so your content stays private.
What is a text similarity checker?
A text similarity checker compares two pieces of text and calculates how similar they are as a percentage. It finds matching sentences, shared phrases and common words. This tool is useful for checking plagiarism between two files, comparing rewritten articles to originals, and verifying that paraphrased content is sufficiently different from the source.
How do I check similarity between two files?
Open both files, copy the text from each, and paste them into the two text boxes above. Click Check Similarity to get an instant comparison. This tool supports any plain text content — essays, articles, reports, code comments and more. For PDF or Word documents, copy the text out first before pasting.
What similarity percentage counts as plagiarism?
There is no universal number. Universities and publishers set their own thresholds, and a high score isn't automatically plagiarism — quotations, references and common phrases also match. Always review what matched and follow your institution's policy.
Does this tool search the internet for plagiarism?
No. This tool compares the two texts you paste directly — it does not search the web or any database. For internet-wide plagiarism checks, tools like Turnitin, Grammarly, or Copyscape are used. This tool is best for document-to-document comparison.
Is my text stored or sent to a server?
No. All comparison happens entirely in your browser using JavaScript. Your text is never sent to any server, stored anywhere, or seen by anyone. This makes the tool completely private and safe for sensitive content.
How is the similarity score calculated?
The tool splits both texts into sentences and checks how many sentences in the checked text have a strong match in the original text. The score is the percentage of checked sentences that closely match the source. It also performs phrase-level matching to catch partial similarities.
How do I compare two Word or PDF documents?
Open each file, copy the text and paste it into the two boxes above. The tool compares the plain text, so formatting, images and tables are ignored.
How can I reduce the similarity score?
Rewrite matched sentences in your own structure and words, add your own analysis, and quote and cite anything you use directly. Simply swapping a few words for synonyms isn't real paraphrasing.
Does quoting and citing count as plagiarism?
Properly quoted and cited text isn't plagiarism, but it will still show up as matching text in any similarity checker. Review matches in context rather than relying on the percentage alone.
Can I compare code with this tool?
You can paste code, but the tool is designed for written text — it compares sentences and phrases — so results for code are only a rough guide.
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