Plagiarism Checker Tool
Check text uniqueness and get tips to avoid plagiarism. Compare text similarity and get writing originality score.
🔗 External Plagiarism Checkers
For checking against the internet, use these trusted tools:
- Grammarly — Free basic plagiarism check
- Copyscape — Best for web content
- Turnitin — Standard for academic use
- Quetext — Good free tier
- DupliChecker — Free for students
About this calculator
Learn what plagiarism is and how to avoid it, and compare two pieces of text to see how similar they are.
This is not a web-wide plagiarism scanner. It compares only the two texts you paste, plus tips for checking online.
How to use it
- Paste Text 1 and Text 2.
- Press Check Similarity.
- Rewrite and cite any overlapping passages.
How similarity is scored
The tool measures overlap in words and phrases (for example, the share of matching word sequences) and reports a similarity percentage. Matching text is not automatically plagiarism: quoted passages with citations are fine, and common phrases will overlap. Professional checkers (Turnitin, Copyscape) compare against databases of web pages and papers. To avoid plagiarism: paraphrase properly, quote with attribution, and cite every source.
Worked example
Interpretation
| Under 10% | Usually fine |
| 10 to 25% | Check matching passages |
| Over 25% | Rewrite or quote and cite |
Tips and common mistakes
- Cite sources even when you paraphrase.
- Use quotation marks for exact words.
- Keep notes of where each idea came from.
- Rewrite structure, not just synonyms.
- Ask your institution which checker it uses.
Frequently asked questions
What is plagiarism?
Presenting someone else's work as your own.
Does 20% similarity mean plagiarism?
Not necessarily; it depends on what matches.
Does this compare against the internet?
No, only the two texts you paste.
How do I paraphrase properly?
Restate the idea in your own structure and cite it.
Are quotations plagiarism?
No, if marked and cited.
Is it free?
Yes.