plagiarism checker

QuillBot's Plagiarism Checker

Scan your document for unintentional plagiarism against billions of sources.

Ensure proper authorship & citations

QuillBot’s Plagiarism Checker analyzes whether any section of your text did not properly attribute authorship to content already published on the web or in books, research papers, academic papers, or news sources.
Real-time report & analysis

Real-time report & analysis

Quickly and accurately review all instances of plagiarized writing in your work with our comprehensive plagiarism score and report.
Clear & actionable feedback

Clear & actionable feedback

Easily understand what sections of your document are missing proper citations.
100+ languages

100+ languages

Scan text in more than 100 languages, such as English, Spanish, French, Portuguese, Arabic, Russian, German, Greek, Chinese, and Japanese.
Monthly scans

Monthly scans

Scan up to 20 pages per month with a Premium subscription. A single page is up to 250 words.

Review your report in 3 easy steps:

Get a subscription
Choose from 1 of 3 Premium plans, giving you access to all of QuillBot’s features.
Upload files
We accept a variety of file types including txt, pdf, docx, and HTML.
View the report
Receive your report in minutes to view potential plagiarism and relevant source links.

Learn best practices around academic integrity

Be Honest
Cite Your
Show Responsibility
Acknowledge Authors
QuillBot is committed to promoting and protecting academic integrity. Our Plagiarism Checker, Citation Generator, and guides are built to educate students on best practices to avoid unintentional plagiarism.

Here’s the thing: even paraphrased writing needs citations. Ideas can be plagiarized just as easily as words, so if you take someone’s idea and reword it, it needs to be cited all the same. Trying to pass off someone else’s idea as your own, with fresh language, is just as unethical as ripping a quote off. Everything that did not originate in your brain needs to be accurately cited.

Our Premium subscription includes the Plagiarism Checker and so much more.


  • 125 words in

  • Standard and
    Fluency modes

  • Limited use of Synonym Slider

  • 1 Freeze Word

  • 1,200 words in Summarizer

  • Faster processing speed

  • Recommended Rewrites

  • Compare Modes

  • Plagiarism Checker

  • Tone insights

  • Paraphraser History

No credit card required


  • Unlimited words in

  • Unlimited Custom and
    8 predefined modes

  • Full use of Synonym Slider

  • Unlimited Freeze Words

  • 6,000 words in Summarizer

  • Faster processing speed

  • Recommended Rewrites

  • Compare Modes

  • Plagiarism Checker
    (20 pages/month)

  • Tone insights

  • Paraphraser History

3-day money-back guarantee


How many pages can I scan per month?
You will receive 20 pages every month with your Premium subscription. Additional pages may be purchased if you need more.
Will my unused pages be carried over to the next month?
If any portion of the standard 20 pages per month is not used, they will not roll over to the next billing period. Additional pages purchased will never expire unless consumed.
Can I buy additional pages as a premium user?
Yes, as a Premium user you are able to purchase more pages. It's $7.45 for 25 pages, $24.95 for 100 pages, and $49.95 for 250 pages. Click here to upgrade to a Premium subscription.
Which file formats are supported by the Plagiarism Checker?
We support the following textual file types: html, txt (UTF-8 encoded), csv, rtf, xml, and htm. We also support the non-textual file types, like pdf, docx, doc, pptx, ppt, odt, chm, epub, odp, ppsx, pages, xlsx, xls, and LaTeX.
How can I find out how many pages have been used?
The total number of pages that can be used for scanning will be displayed in the Plagiarism Checker, and the number of pages scanned will show up in your Plagiarism Report.
Does QuillBot save my documents?
QuillBot stores your content in order to run the plagiarism report, so you can access your reports in the future. Our third-party vendor, CopyLeaks, does not store your content. QuillBot will never share your content with any third parties outside of CopyLeaks.
Do I need a premium account to use the Plagiarism Checker?
Yes. All Premium users have access to the Plagiarism Checker.