As covered in previous articles and videos, there is a comprehensive guide on how to access Turnitin's Self-Check Facility and how to use it. The aim of using this facility is to access a similarity score.

A similarity score represents the percentage proportion of matched text to total text submitted in your document. Matched text can consist of cited or quoted text from other articles in Turnitin's database and bases a score on whether proper citation or quotation requirements have been inserted.
Similarity score highlighted

Your similarity score threshold is very context specific to the particular assignment or module being completed. The requirements of source materials and references quota depends on assignment and this influences your overall similarity score.

A lower similarity score generally represents higher originality in work completed and a high score may require reworking of content.
However, requiring heavy citations and sources within an assignment as instructed may be a prerequisite to a higher similarity score, which will be taken into account when marking submission within Turnitin.


A similarity report is a version of your submission that has been overlaid with the details of text matches identified by Turnitin when it compared your work against its reference sources and databases. Each of the matches can be interrogated to see details of the identified sources that have been matched.

You can see the similarity report when you open your similarity check submission. You can step through each of the identified matches. This allows you, firstly, to see what parts of your work are contributing to the similarity score dismayed, then to confirm that you have used proper referencing and citations for matching materials and finally, to investigate if you need to revise your writing to address missing citations or better paraphrase.

Keep in mind that there will normally be some degree of similarity in all your work. When you review the similarities, you have the opportunity to check that you have correctly quoted and referenced these matches so that you are demonstrating your awareness and ability to apply good academic practices.


Viewing your similarity report:

  1. Access your Turnitin submission that you wish to review similarity on.

    Similarity score menu

  2. Click on the blue title link to open the similarity report menu.Blue title turnitin file highlighted to access similarity report
  3. It may take a few moments to open and generate the similarity report as Turnitin is a plug-in extension of Moodle. By default the report may open on the Feedback tab. This is not relevant as of now so open the Similarity tab.
    Similarity tab highlighted


  4. In the Similarity tab, the content within your submission has text highlighted.Text highlighted red due to similarity

  5. The panel that appears on the right displays the overall similarity score.


  6. The right-hand panel demonstrates two options: Match Groups and Sources tabs. Match Groups tab provides similarity percentage divided into four self-explanatory headings. Each heading has an associated similarity score.
  7. Clicking on each of these headings expands further detail at lower section of the panel. In this lower section, each item again indicates its similarity contribution and also gives the details of the matched source by pressing the expand button.
     expanded similarity panel in similarity menu


  8. An alternative way to investigating matches is by clicking on highlighted text to display match quantity and detail in the left panel.
  9. It is possible to exclude matches if text displays from an unassociated source. This can be completed by expanding the match in the left panel and pressing the exclude match button.exclude match highlighted in similarity menu

  10.  This exclusion will be noted under overall similarity score and you can now see your refreshed lower similarity score.
    Reduced similarity score due to excluded source

Click the below link to view a step-by-step video of the full process of obtaining a similarity report view: