Best Free Plagiarism Checking Sites

Best Free Plagiarism Checking Sites
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Plagiarism is an age-old problem. 

The word, derived from the Latin plagiarius ("kidnapper"), dates back to 17th-century English. Much earlier than that, in the first century, the Roman poet Martial used “plagiarius” to castigate another poet whom he accused of appropriating his words. 

How We Test: Each site included here was tested using passages of 150-200 words on these topics: plagiarism (Wikipedia), George Washington (Wikipedia), and Romeo and Juliet (Cliffsnotes). Sites that didn’t recognize the copied text were deemed unreliable and therefore excluded.

In our modern world, however, the ability of students to find and copy others’ work is greater than ever before. While there are a number of in-depth and effective paid solutions that allow educators to verify the originality of student work, there are only a few free solutions that are worth trying.  

We have compiled the best free online plagiarism checkers. Several share a very similar interface and ad profile, suggesting a common parent company. Regardless, all were able to reliably identify the plagiarized passages and identify a source.  

Best Free Plagiarism Checking Sites for Teachers Plagiarism Detector
No account is required to quickly upload documents or paste text (up to 1,000 words) in Search Engine Reports. Paid accounts from $10 to $60 monthly provide premium features and allow word counts of 35,000 to 210,000. 

Check Plagiarism
Check for plagiarism efficiently with this user-friendly site. Whether you want to scan a text or upload a file, this tool will search for any plagiarized content. Sign up for a free account to access a comprehensive report that includes sources and exact matches. Educators can run up to 200 plagiarism queries and receive grammar and SEO feedback. For additional features and unlimited checks, users can upgrade to a paid account.  

Dupli Checker
Dupli Checker furnishes a hassle-free plagiarism-checking experience. With no account needed, users can check for plagiarism once daily. To access unlimited plagiarism checks and additional features such as downloading Word or PDF plagiarism reports, create a free account. In addition to its plagiarism checking tools, Dupli Checker also provides a set of free, entertaining, and useful text and image tools such as the reverse text generator, favicon generator, and MD5 generator.

While PapersOwl focuses mainly on essay writing, it also offers a free plagiarism-checking tool. Users can simply paste their essays or website content into the tool, or upload supported files such as .pdf, .doc, .docx, .txt, .rtf, and .odt files. Although the website allows students to pay for essays, it's worth noting that their plagiarism checker is genuinely free and can be used to validate the originality of any submitted work.

Plagiarism detector
Easily check for plagiarism without creating an account, then download the pdf report file at no charge. The site accommodates multiple languages, while allowing unlimited free checks of text up to 1,000 words. Flexible premium accounts are available on a weekly, month or yearly basis. 

A fairly simple site in which users paste text of up to 1,000 characters and receive free Quick Search results. Easy to use and no account is required. Click on your results to see the matching text conveniently highlighted and presented side by side. Flexible paid plans range from $1 to $100, and support deeper searching and analysis. 

With a clean, well-designed interface, it’s a pleasure to use Quetext. After the first free search, you’ll need to create a free account. Unlike many other plagiarism sites, Quetext makes it easy to compare the free and pro offerings -- free accounts allow 2,500 words monthly, while the paid Pro account allows 100,000 words, plus deeper search capability. 

Small SEO Tools
Teachers can check for plagiarism in texts up to 1,000 words without creating an account. Accepted file types include: .tex, .txt, .doc, .docx, .odt, .pdf, and .rtf. This platform offers an array of other useful text tools, from word counter to text-to-speech generator to image-to-text generator. One of the most unusual is the English-to-English translation tool, which helps users convert American English to British English and vice-versa. Could come in handy if a friend says, “It’s brass monkeys out there, and now I need to spend a penny. Cor blimey, this day turned into a damp squib!”

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Diana Restifo

Diana has been Tech & Learning's web editor and contributor since 2010, dedicated to ferreting out the best free tech tools for teachers.