Scribbr’s free plagiarism checker estimates the risk of plagiarism by calculating the percentage of text in your document that’s similar to other sources.
A moderate or high risk of plagiarism means that the plagiarism software detected several similarities worth reviewing.
Note that similarities are not necessarily plagiarism. You will need to decide on your own whether your text needs revision or citation.
Information can often be found in more than one place. For this reason, other sources citing the same information you used can come up in your Sources Overview.
The important thing is to make sure you’ve cited the source of the material. Try to find the original source, but if you can’t find it, it’s best to cite the source where you found the information.
Similarities in your document are highlighted for quick and easy review. Each color corresponds to a source in your Sources Overview at the right side of your report.
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.
No, you will never get a 100% match because the Scribbr Plagiarism Checker does not store documents in a public database.
You can change the settings of your report by clicking on the gear icon which is displayed just above the similarity score.
The settings allow you to exclude search repositories or ignore small matches, quoted material, or references in your bibliography.
Are you not satisfied with the results of the Scribbr Plagiarism Checker, or are you experiencing difficulties with the document? Find out what to do when…
If you copied a fragment from a source and the Plagiarism Check did not find it, there are four possible explanations.
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 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.
To cater to this, we have the Self-Plagiarism Checker at Scribbr. Just upload any document you used and start the check. You can repeat this as often as you like with all your sources. With your Plagiarism Check order, you get a free pass to use the Self-Plagiarism Checker. Simply upload them to your similarity report and let us do the rest!
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.
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!
Yes, Scribbr offers a limited free version of its plagiarism checker in partnership with Turnitin. It uses Turnitin’s industry-leading plagiarism detection technology and has access to most content databases.
If you’re a university representative, you can contact the sales department of Turnitin.
Scribbr’s Plagiarism Checker is powered by elements of Turnitin’s Similarity Checker, namely the plagiarism detection software and the Internet Archive and Premium Scholarly Publications content databases.
The add-on AI detector is powered by Scribbr’s proprietary software.
Your document will be compared to the world’s largest and fastest-growing content database, containing over:
Note: Scribbr does not have access to Turnitin’s global database with student papers. Only your university can add and compare submissions to this database.
Scribbr’s plagiarism checker offers complete support for 20 languages, including English, Spanish, German, Arabic, and Dutch.
The add-on AI Detector and AI Proofreader are only available in English.
The complete list of supported languages:
If you purchased a Plagiarism Checker in combination with our Proofreading & Editing service, you can start the Plagiarism Checker anytime at your convenience.
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.
No, your teacher, professor, or admissions officer will not be able to see your submissions at Scribbr because they’re not added to any shared or public databases.
Your writing stays private. Your submissions to Scribbr are not published in any public database, so no other plagiarism checker (including those used by universities) will see them.
If your university uses Turnitin, the result will be very similar to what you see at Scribbr.
The only possible difference is that your university may compare your submission to a private database containing previously submitted student papers. Scribbr does not have access to these private databases (and neither do other plagiarism checkers).
To cater to this, we have the Self-Plagiarism Checker at Scribbr. Just upload any document you used and start the check. You can repeat this as often as you like with all your sources. With your Plagiarism Check order, you get a free pass to use the Self-Plagiarism Checker. Simply upload them to your similarity report and let us do the rest!
Yes, if you are interested in buying more than 25 plagiarism checks, please fill in this form. We will get back to you within the next two working days!
For questions, please do not hesitate to reach out to info@scribbr.com.
You can download or print your plagiarism report using the “Share” button in the bottom-left corner of your plagiarism report.
Sometimes the Scribbr Plagiarism Check finds similarities that are not forms of plagiarism, such as references and correctly cited sources. You can exclude these irrelevant similarities from your total similarity score.
Exclude similarities:
Step 1: Open your Plagiarism Check results.
Step 2: Click on the highlighted similarity that you would like to exclude.
Step 3: Click on the “Exclude” button on the right.
The similarity is now excluded from your total similarity score.
If you have excluded multiple sources from your total similarity score, then you might see an error message in your Plagiarism Check results. Unfortunately, this is a problem that we cannot fix at the moment.
If you encounter this issue, you can simply ignore all irrelevant similarities and subtract their score from your total similarity score. This allows you to calculate your actual similarity score by yourself.
Review every similarity for plagiarism, and decide whether or not you need to revise your text.
If you accidentally uploaded the wrong document to the Plagiarism Checker, Scribbr will not refund you for this check or give you a discount for another check. The check starts automatically upon payment, which is why we cannot change your document anymore.
A similarity score of 0% means that our plagiarism software didn’t find any similarities between your document and other documents in our database.
On average, only 1 out of 150 students achieve this. Congratulations!
Your work should not contain any plagiarism. Even if your score is 1%, you will need to review each similarity and decide whether it’s necessary to revise your work.
But contrary to popular belief, plagiarism checkers work by detecting similarities, not plagiarism. Not all similarities are plagiarism. Similarities can be:
Your similarity score shows you what percentage of your text is found within sources in the comparison database.
For example, if your score is 15%, then 15% of the content you wrote is unoriginal, as it matches text in the database.
You will have to review each similarity and decide whether or not you need to revise your work.
If you’re unable to view the Plagiarism Check results in your browser, please try the following two solutions:
1. Are you using Google Chrome?
We’ve found that using Google Chrome resolves most issues related to the results page. First, try using Google Chrome to open your Plagiarism Check results. If you are already using Google Chrome, or if this solution does not work, then proceed to the second solution.
2. Contact support for a PDF copy of the results.
If the first solution doesn’t work, you can contact our support team via chat or email and request a PDF copy of the results via email. This way, you can still review and process the results. We apologize for the inconvenience.
Scribbr checks your document for plagiarism only once. You can use the “exclude text” feature to exclude similarities that you’ve resolved, which automatically updates your similarity score.
If you would like to recheck your entire document, you can purchase a new plagiarism check at the regular price. We don’t currently offer a subscription service.
Sometimes a quote is marked as a similarity by the Scribbr Plagiarism Checker. A quote is not a form of plagiarism, but you do have to ensure you have properly cited the original source.
If you’re certain that you have correctly quoted and cited, you can exclude the similarity from your plagiarism score.
Below we briefly explain the rules for quoting in APA Style.
When quoting fewer than 40 words, use double quotation marks around the quote, and provide an APA in-text citation that includes the author, the year, and a page number or range.
If the quote contains 40 words or more, format it as a block quote, which begins on a new line and is indented in its entirety. Include an in-text citation after the period.
Sometimes it is necessary to quote a source at length:
The Scribbr Plagiarism Checker detect similarities between your paper and a comprehensive database of web and publication content. Because many students write their references in the same way (for instance in APA Style), a plagiarism checker finds many similarities with these sources.
A reference found by the check is not a form of plagiarism. Therefore, there is no need to take action.
You can exclude matches from your reference list in your Plagiarism Check results. However, please be aware that this might not always work, depending on your document.
Step 1: Open your Plagiarism Check results.
Step 2: Click the settings button in the “Sources overview” (see picture below).
Step 3: Select exclude reference list (see picture below).
Step 4: Click “Done.”
No worries! This error does not influence the accuracy of your Plagiarism Check results.
If you have inserted a chapter or section title in the header of your document, then you might see an error message in your Plagiarism Check results.
Instead of the title, you will see an error message like the one above. Unfortunately, this is a problem that we cannot fix.
Our check may flag these error messages as similarities. You can ignore these similarities.
No worries! This error does not influence the accuracy of your Plagiarism Check results.
If you have an automatic table of contents and/or list of figures and tables, then you might see an error message instead of the page numbers. The error message might look like this: “Error! Bookmark not defined.”
Unfortunately, this is something we cannot fix. Our check may flag these error messages as similarities. You can ignore these similarities.
The Scribbr Plagiarism Checker is able to work with the following file formats:
The format you use doesn’t influence the final result. If you’re working with a format not listed here, we recommend converting it prior to submitting.
At the moment we do not offer a monthly subscription for the Scribbr Plagiarism Checker. This means you won’t be charged on a recurring basis – you only pay for what you use. We believe this provides you with the flexibility to use our service as frequently or infrequently as you need, without being tied to a contract or recurring fee structure.
You can find an overview of the prices per document here:
| Small document (up to 7,500 words) | $19.95 |
|---|---|
| Normal document (7,500-50,000 words) | $29.95 |
| Large document (50,000+ words) | $39.95 |
Please note that we can’t give refunds if you bought the plagiarism check thinking it was a subscription service as communication around this policy is clear throughout the order process.
By default, the plagiarism report only shows similarities of 9 words or more.
You can change the minimum length of a similarity yourself in order to exclude small matches from the plagiarism report.
The ideal minimum length of similarities is different per case. In general, we believe that setting the minimum to 8 words results in too many small similarities that are unlikely to be plagiarism. That’s why the default value is set to 9.
However, if you believe that your document contains many small similarities that are not plagiarism (like these), you can try changing the setting to 10 or 11 to get a more accurate view of the potential plagiarism in your document.
Proceed with caution, since increasing the number might hide potential plagiarism in your report.
1) Click on the gear icon on the top right of the plagiarism report
2) Fill in your desired minimum similarity length
3) Click “Done” to go back to the “Sources overview”
For most people, there is no need to change this value. However, if you want more control over the similarities shown in your report and you think that most of the small similarities are not relevant, you can increase this number.
Please proceed with caution, since increasing this number might hide potential plagiarism in your report. Decreasing the value is not recommended.
If you decrease this number, shorter similarities will be included in the report. This means you will see more similarities and a higher similarity percentage.
However, most of these extra similarities are unlikely to be instances of plagiarism. Short similarities are often the result of common phrases that appear in many different sources.
If you increase this number, only longer similarities will be included in the report. This means you will see fewer similarities and a lower similarity percentage.
Since the similarities are longer, the similarities you now see are more likely to be plagiarism.
However, by excluding the smaller similarities, you might miss some instances of potential plagiarism.
Our team helps students graduate by offering:
Scribbr specializes in editing study-related documents. We proofread:
Scribbr’s Plagiarism Checker is powered by elements of Turnitin’s Similarity Checker, namely the plagiarism detection software and the Internet Archive and Premium Scholarly Publications content databases.
The add-on AI detector is powered by Scribbr’s proprietary software.
The Scribbr Citation Generator is developed using the open-source Citation Style Language (CSL) project and Frank Bennett’s citeproc-js. It’s the same technology used by dozens of other popular citation tools, including Mendeley and Zotero.
You can find all the citation styles and locales used in the Scribbr Citation Generator in our publicly accessible repository on Github.
