How Turnitin Works

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Every time you submit an assignment at Melbourne Law School, you’re using software on the LMS called Turnitin.


Turnitin is plagiarism detection software. It retains a copy of every assignment that has ever been submitted to it, from universities all over the world. Its vast database also contains copies of academic articles and books that you’re likely to use during your research.

This means that Turnitin can automatically check your work against billions of pre-existing documents. It conducts this check to see which parts of your work match other sources.

Turnitin has highlighted the parts of this student’s essay that are a match for text in its database.

But just because parts of an essay might match another source doesn’t automatically mean that there has been plagiarism! For example, directly quoting from a journal article will not constitute plagiarism so long as you’ve included an appropriate citation.

So how does it work?

When you submit an assignment to Turnitin, it generates an originality report for your teacher. This report highlights the parts of your assignment that match a pre-existing source in Turnitin’s database. It also displays an overall similarity index for your assignment.


If this similarity index is high enough, your assignment may be reviewed by the University to ensure that plagiarism has not occurred.

What if the Turnitin report says that a high percentage of my assignment matches other sources, but I haven’t included footnotes or references for those parts?

Whether intentional or not, this is probably an instance of plagiarism and there may be an investigation.

The last sentence in this paragraph includes a citation. The sentence before that, however, appears to have been copied directly from the same source and includes neither a reference nor quotation marks. Because it is attempting to pass another person’s writing off as the student’s own, this is plagiarism.

But what if I’m using a lot of long quotes and that’s why the report says a high percentage of my assignment has been copied?

Long quotes may result in a high similarity percentage on the Turnitin Report. As long as you’ve correctly referenced the sources of the quotes, however, this will not be plagiarism. Nonetheless, there are plenty of other good reasons to avoid overusing long quotes in your work!

Does that mean as long as I always include a citation, it doesn’t matter if my assignment’s similarity index is high?

Not necessarily. The originality report will also show your teacher the names of sources you’ve copied or quoted text from.


If your teacher then goes back into that assignment and sees that your citation and Turnitin’s source don’t match up, this may warrant an investigation. That’s why it’s so important to always cite the genuine source of your information. If you’ve lost track of where you found something, take the time to go back and get it right!

I’m worried because there are some compulsory parts of my assignment that will probably be a match.

It’s true that some parts of your assignment will always come back as a match. The essay topic or the assessment cover sheet, for example, are likely to be flagged as a match because other students in your class, or in previous years, have submitted assignments containing the same text. Your teacher knows this and, should those parts of your assignment be highlighted, they will discount that part of the Turnitin report.

Can I check the report for my assignment before I formally submit it?

While some universities allow students to check the Turnitin report for their assignment before submitting it, Melbourne Law School does not. The best way to make sure that your assignment will meet academic integrity standards is to write original work and to correctly reference any external sources you’ve relied on.

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