Turnitin
Turnitin is an Internet-based similarity detection service run by the American company Turnitin, LLC, a subsidiary of Advance Publications. The software as a service website allows users to check submitted documents against its database and the content of other websites to identify plagiarism. As of 2025, the company licenses access to its services to over 16,000 universities and high schools worldwide, with more than 71 million students enrolled.
In the UK, the service is supported and promoted by JISC as "Plagiarism Detection Service Turnitin UK". The Service is operated by iParadigms, in conjunction with Northumbria Learning, the European reseller of the service.
Company history
Turnitin originated in 1994 at the University of California, Berkeley, where graduate student John M. Barrie developed an online peer-review system that later evolved into plagiarism-detection software. To commercialize the system, he and collaborators Christian Storm, Emmanuel Briand and Melissa Lipscomb established iParadigms LLC in 1996.Development of the Turnitin platform progressed over the next several years. The company introduced the Turnitin service in 1998, launched its precursor site Plagiarism.org to the public in April 1999, and released Turnitin.com more broadly in early 2000.
In 2018, Turnitin acquired the plagiarism-detection service VeriCite, expanding its presence among U.S. higher-education institutions. The following year, it was purchased by Advance Publications for US$1.75 billion, marking one of the largest acquisitions in the educational-technology sector at the time. Turnitin continued to broaden its reach by acquiring Unicheck in 2020 and Ouriginal in 2021, the latter formed from the merger of Urkund and PlagScan. These additions consolidated Turnitin’s position as a leading provider of academic-integrity and text-matching software worldwide.
Functionality
The Turnitin software checks for potentially unoriginal content by comparing submitted papers to several databases using a proprietary algorithm. It scans its own databases and also has licensing agreements with large academic proprietary databases.Results can identify similarities with existing sources and can also be used in formative assessment to help students learn to avoid plagiarism and improve their writing.
Turnitin, LLC also runs the informational website plagiarism.org and offers a similar plagiarism-detection service for newspaper editors and book and magazine publishers called iThenticate. Other tools included with the Turnitin suite are GradeMark and PeerMark.
Artificial intelligence content detection
In early 2023, Turnitin released a feature that aims to detect content generated by artificial intelligence applications like ChatGPT; however, the accuracy of AI content detection remains a topic of debate.Later that year, some schools disabled Turnitin's AI detection software due to concerns that, like all other AI detection tools the software is not entirely accurate. Concerns arose after cases were brought with students alleging Turnitin falsely accused them of using AI. This has happened when students use the grammar-correcting software Grammarly, which is recommended for student use by many schools. Turnitin says that they believe about 1% of the papers they flag as AI-written were actually written by humans, and that a much higher rate is generated by AI but not flagged.
Student-paper database
The essays submitted by students are stored in a database used to check for plagiarism. This prevents one student from using another student's paper by identifying matching text between papers. In addition to student papers, the database contains a copy of the publicly accessible Internet, with the company using a web crawler to add content to Turnitin's archive continually. It also contains commercial and/or copyrighted pages from books, newspapers, and journals.As of June 2025, the company's student-paper database contained 1.9 billion submissions.
Classroom integration
If requested by teachers, students can upload their papers directly to the service for teachers to access them there. Teachers may also submit student papers to Turnitin.com as individual files, by bulk upload, or as a ZIP file. Teachers can further set assignment-analysis options so that students can review the system's "originality reports" before they finalize their submission. A peer-review option is also available.Some virtual learning environments can be configured to support Turnitin, so that student assignments can be automatically submitted for analysis. Blackboard, Moodle, ANGEL, Instructure, Desire2Learn, Pearson Learning Studio, Sakai, and Studywiz integrate in some way with the software.
Admissions applications
In 2019, Turnitin began analyzing admissions application materials through a partner software, Kira Talent.Reception
Students may be required to submit work to Turnitin as a requirement of taking a certain course or class. The software has been a source of controversy, with some students refusing to submit, arguing that requiring submission implies a presumption of guilt. Some critics have alleged that the use of this proprietary software violates educational privacy as well as international intellectual-property laws, and exploits students' works for commercial purposes by permanently storing them in Turnitin's privately held database.Privacy
The Student Union at Dalhousie University has criticized the use of Turnitin at Canadian universities because the American government may be able to access the submitted papers and personal information in the database under the USA PATRIOT Act. Mount Saint Vincent University became the first Canadian university to ban Turnitin's service partly because of implications of the Act.Copyright violation concerns
Lawyers for the company claim that student work is covered under the theory of implied license to evaluate, since it would be pointless to write the essays if they were not meant to be graded. That implied license, the lawyers argue, thus grants Turnitin permission to copy, reproduce, and preserve the works. The company's lawyers further claim that dissertations and theses also carry with them an implied permission to archive in a publicly accessible collection such as a university library.University of Minnesota Law School Professor Dan Burk countered that the company's use of the papers may not meet the fair-use test for several reasons:
- The company copies the entire paper, not just a portion
- Students' work is often original, interpretive, and creative rather than just a compilation of established facts
- Turnitin is a commercial enterprise
Presumption of guilt
Some students argue that requiring them to submit papers to Turnitin creates a presumption of guilt, which may violate scholastic disciplinary codes and applicable local laws and judicial practice. Some teachers and professors support this argument when attempting to discourage schools from using Turnitin.WriteCheck
iParadigms, the company that once owned Turnitin, ran another commercial website called WriteCheck. On this website, students pay a fee to have a paper tested against the database used by Turnitin to determine whether or not that paper would be detected as plagiarism when the student submits that paper to the Turnitin website. It was announced that the WriteCheck product was being withdrawn in 2020 with no new subscriptions being accepted after November 2019. The economist Alex Tabarrok has complained that Turnitin's systems "are warlords who are arming both sides in this plagiarism war". The website is no longer active.Litigation
In one well-publicized dispute over mandatory Turnitin submissions, Jesse Rosenfeld, a student at McGill University declined, in 2004, to submit his academic work to Turnitin. The University Senate eventually ruled that Rosenfeld's assignments were to be graded without using the service. The following year, another McGill student, Denise Brunsdon, refused to submit her assignment to Turnitin.com and won a similar ruling from the Senate Committee on Student Grievances.In 2006, the Senate at Mount Saint Vincent University in Nova Scotia prohibited the submission of students' academic work to Turnitin.com and any software that requires students' work to become part of an external database where other parties might have access to it. This decision was granted after the students' union alerted the university community of their legal and privacy concerns associated with the use of Turnitin.com and other anti-plagiarism devices that profit from students' academic work. This was the first campus-wide ban of its kind in Canada, following decisions by Princeton, Harvard, Yale and Stanford not to use Turnitin.
At Toronto Metropolitan University in Toronto, students may decide whether to submit their work to Turnitin.com or make alternate arrangements with an instructor.
Similar policies are in place at Brock University in Saint Catharines.
On March 27, 2007, with the help of an intellectual property attorney, two students from McLean High School in Virginia and two students attending Desert Vista High School in Phoenix, Arizona, filed suit in United States Circuit Court alleging copyright infringement by iParadigms, Turnitin's parent company. Nearly a year later, Judge Claude M. Hilton granted summary judgment on the students' complaint in favor of iParadigms/Turnitin, because they had accepted the click-wrap agreement on the Turnitin website. The students appealed the ruling, and in 2009, the United States Court of Appeals for the Fourth Circuit affirmed Judge Hilton's judgment in favor of iParadigms/Turnitin.