For all work submitted using Turnitin, Turnitin generates a similarity score. This is a percentage between 0-100%, indicating how much of a student’s written work matched text from other sources. This report also includes a highlighted, color-coded version of the student’s original submission, showing which passages match other sources, and what those sources were.
Detailed information on Similarity Reports is available from Turnitin Help: Interpreting the Similarity Report
Does a high similarity score always indicate plagiarism? Does a low similarity score indicate that there was not any plagiarism?
A very high number can indicate academic integrity issues. However, even essays generating a low similarity score may still have problematic material. For example, an essay with a similarity score of 20% could include a long, uncited passage from another source, which would generally constitute plagiarism; the same score could also indicate that the student had used similar phrases and sentence mechanics as other authors, in a way that did not indicate any academic integrity issues. Faculty using Turnitin are strongly encouraged to review Similarity Reports in detail, rather than relying only on the numeric score assigned.
What do the colored flags next to each similarity score indicate?
Turnitin assigns a colored flag to each Similarity Report. These flag colors indicate the following:
- Blue: No matching text
- Green: One word to 24% matching text
- Yellow: 25-49% matching text
- Orange: 50-74% matching text
- Red: 75-100% matching text
Faculty are strongly encouraged to review Similarity Reports in detail, rather than relying entirely on similarity scores. Although a blue flag indicates a very low possibility of plagiarism, and a red flag indicates a very high possibility of plagiarism, Turnitin Similarity Reports may potentially include “false positives,” where common phrases or quoted materials are misidentified as possible incidents of academic misconduct.