What is Turnitin?

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Turnitin is a web-based similarity detection service and academic integrity tool which is available to any member of staff with the role of teacher or administrator in QMplus. Turnitin compares submissions against an extensive database containing a diverse array of academic and non-academic content.

How does Turnitin work?


A Turnitin assignment is set up by a lecturer or a QMplus administrator from within a school. Students access this assignment online and upload their work before the due date. Turnitin will then analyse the submitted work to identify text matches with other sources, usually completing this task within a few minutes. Sources checked include websites, books, journals and student work that has previously been submitted to Turnitin.

Staff can view the work that has been submitted and there is also an option to mark the work online and include grades and comments, which can be returned to the student once all papers have been marked.

For each piece of submitted work, Turnitin provides two things:

  • similarity index, which indicates the percentage of the submitted paper that Turnitin has identified as being matched against other sources;
  • An originality report, which shows each of these matches in more detail, including the precise location within each source that Turnitin has found.

Things you should know


  • The most important thing to understand about Turnitin is that it does not identify plagiarism; instead it provides a report that allows students and staff to see where similarities have occurred. To determine whether there are grounds for further investigations, staff would need to review the Turnitin report in detail and use their academic judgement.
  • A high similarity index does not immediately indicate plagiarism and a low similarity index may not indicate original work.
  • A 15% match might be made up of many short phrases scattered throughout the assignment and may not be a concern. Alternatively, the 15% could represent a few paragraphs that are copied.
  • In many subjects, learning the ‘language of the discipline’ is part of the process that students undertake to develop as academic writers. As a result, it is highly likely – perhaps even desirable – that some matches will occur.
  • The nature of the assignment and the discipline can also affect the level of matching.
  • Departments sometimes identify a threshold similarity index, with student work having a similarity index higher than this threshold being checked more thoroughly. This can be a useful way of managing workload and prioritising assignments for further investigation. However, it may not be advisable to set such limits for students, since it can give them the impression that the university condones low levels plagiarism or encourage them to focus only on reducing the similiar index, not developing good academic writing skills.
  • When work is submitted to Turnitin, it is usually stored within the Turnitin database so that it can be cross-checked against future submissions from other UK universities. The students retain the copyright and intellectual property of all work that they submit. The developers of Turnitin also work closely with the UK Information Commissioner’s Office to ensure that student work is used fairly and legally.
  • The Turnitin database is very large and growing. Turnitin has agreements with many major publishers to include books, journal articles and conference proceedings when they are published. There is also an ongoing project to include many older, out-of-print and back-catalogue books and articles. However, Turnitin does not contain every word ever written, and so may miss some matches even where text has been copied from another source.
  • If assignments contain a high proportion of images, graphs, software coding, formulae or audio, Turnitin may be less useful, because it is only able to match text.
  • Turnitin is not a replacement for academics or for the tools that they have traditionally used to identify similarity. However, it can reduce the time spent on investigating possible cases of plagiarism.