Extensive testing proves that Scribbr’s plagiarism checker is one of the most accurate plagiarism checkers on the market in 2022.
The software detects everything from exact word matches to synonym swapping. It also has access to a full range of source types, including open- and restricted-access journal articles, theses and dissertations, websites, PDFs, and news articles.
you are not satisfied with your similarity score:The similarity score shows you what percentage of your text the software found in sources in the Turnitin database. That means we cannot change your score.
If you copied a fragment from a source and the Plagiarism Check did not find it, there are four possible explanations.
You paraphrased the fragment
If you paraphrased the original text by using different words and/or changing their order, the fragment will no longer be detected by the plagiarism software.
You can test this by searching the fragment in double quotation marks on Google. If no results are returned, you successfully paraphrased. Note that you still need to cite the source of the original idea.
However, if Google did return a result but our software did not highlight it, this might mean that…
The source is not part of our database
The Turnitin database used by the Scribbr Plagiarism Checker contains 99.3 billion current and historical webpages and 8 million journal articles and books. However, it’s possible that the source you used is an inaccessible publication or a student paper that is not part of our database.
Even if you’re certain that the source is publicly accessible, it might not yet have been added to the database. Turnitin is constantly updating its database by searching the internet and adding new publications. You can expect the source to be added in the near future.
The “Exclude Small Matches” number is set too high
By default, the plagiarism report shows similarities of 9 words or more. If the fragment you copied is shorter than that, it will not be shown in the report.
You can manually adjust the minimum length in order to show shorter similarities. Find out how to do that here.
Your document was not readable
If you uploaded a PDF file, it is possible that your document is not machine readable or was converted to an image instead of text. As a result, no similarities will be found.
To test if the text in your PDF is readable, you can copy and paste the document into a text editor (e.g. Microsoft Word, Notepad, TextEdit). If the text editor shows the same text as the PDF, then the text will also be readable by our plagiarism software.
If you know that you used a fragment, but it wasn’t found by our plagiarism software, it’s best to paraphrase or quote it anyway (and be sure to cite the source). It’s always better to be safe than sorry!
Scribbr recommends using the Plagiarism Checker after you have received your document and gone through all of the edits. Then you can upload the most recent version of your paper and avoid having to manually transfer changes from one document to another.