Key Points
- Turnitin is a powerful tool in academia to detect plagiarism, but it doesn’t necessarily mean you plagiarized if it detects similarity in your paper.
- The acceptable level of Turnitin similarity score varies between teachers and assignments.
- Turnitin can detect bad rephrasing or paraphrasing, even if you don’t copy a text word-for-word.
- Turnitin uses a color-coded system to indicate the similarity score, with red indicating the highest level of similarity.
- Turnitin compares your paper with a large database of existing works, including academic papers and content scraped from websites.
Turnitin is one of the most powerful tools in academia to weed out plagiarism. But for new students who have no experience with plagiarism detectors, it can often create concern or even panic. The truth is that everyone’s paper will have some level of similarity to other works. However, Turnitin detecting some similarity doesn’t mean that you plagiarized or did anything wrong.
Most teachers have a percentage that they deem acceptable. Even that can vary between teachers, as well as each assignment. However, what is potentially more concerning for many students is Turnitin’s ability to detect AI-written papers. With the growing prevalence of artificial intelligence, schools are focusing more heavily on academic integrity than ever before.
Let’s break down what you need to know to stave off any panic.
What is a High Turnitin Similarity Score?
A Turnitin score does not indicate that you plagiarized a paper. But if you have to put a number on it, most teachers consider a similarity score below 25% acceptable.
However, this will vary depending on the assignment. For instance, an essay about your life or personal experiences without citations should have very little similarity to any existing works.
In contrast, a book report on a popular novel will likely have a high(er) Turnitin similarity score. In this case, it is more important to use proper quotations and citations throughout your work rather than worrying about the score. Another thing to remember is that common sentences and phrases will also get flagged by Turnitin but do not necessarily represent plagiarism.
By now, you may be wondering what constitutes plagiarism and when to worry about it. In short, plagiarism is the act of turning in someone else’s work as your own. This can include directly copying an entire paper, excerpts, or even bad paraphrasing.
It is best to ask your teacher directly to get an exact answer, but remember that each teacher at your school may have a different answer.
What Do Turnitin Similarity Scores Mean?
The Turnitin similarity score indicates what percentage of the essay matches other documents. After submitting your first paper, you may be surprised that similarities were detected. Most of the time, the similarity is nothing to worry about as Turnitin often flags common phrases and quotes.
Turnitin can often detect bad rephrasing or paraphrasing, even if you don’t copy a text word-for-word. It is important to remember that Turnitin detects similarities rather than actual plagiarism. Teachers then double-check the flagged parts of the text to ensure that it is not plagiarism.
Turnitin Color Scores
After submitting a paper through Turnitin, the system analyzes your document to search for similarities. This process typically takes a few minutes, but once complete, you will get a score and a color. Turnitin uses a color-coded system to help illustrate the similarity score.
The lowest rating (least plagiarized) is blue, which means the paper has no similar sentences. From there, it goes to green, yellow, orange, and red (most plagiarized). The highest tier indicates that matches were found for nearly every sentence in the paper.
Check out the table below for a full list of all the tiers and colors used in Turnitin’s similarity report.
Color | Similarity Percentage |
---|---|
Blue | 0% |
Green | ≤24% |
Yellow | 25% – 49% |
Orange | 50% – 74% |
Red | 75% – 100% |

©fizkes/Shutterstock.com
How Does Turnitin Detect Plagiarism?
Turnitin detects plagiarism by comparing your paper with a large database of existing works. Much of the database consists of other papers uploaded to Turnitin since it stores every document that is uploaded to its system. In addition to the company’s own repository, Turnitin also scrapes websites for content.
This is important because it allows Turnitin to find a wide range of works beyond academic papers. Besides looking for exact matches, Turnitin uses a proprietary system to identify words and phrases that may have been copied, even if the words are not an exact match. When the program detects a similar work in your paper, it leaves a note with a link to the matched document.
Wrapping Up
Turnitin is a powerful tool that is critical to protecting academic integrity. However, it is also a source of concern for many students. To alleviate that concern, make sure that you submit work that is 100% your own and that all quotations are properly cited.
If you still have concerns about Turnitin similarity scores, take a minute and ask your teacher or a teaching assistant.
The image featured at the top of this post is ©fizkes/Shutterstock.com.