The best plagiarism checkers of 2019 [in-depth comparison]
The plagiarism checkers listed in this article are tested using two test documents:
- Student’s paper with 50% plagiarism
- 100% plagiarized text with excerpts from journals, books and websites.
The table below shows an ordered list of the top 10 best plagiarism checkers in 2019. The overall score is based on plagiarism detected, usability and accuracy.
Tests show that the Scribbr Plagiarism Checker is the best plagiarism checker on the market. It is able to detect exact similarities and difficult-to-detect paraphrasing plagiarism, while keeping false positives to a minimum. The plagiarism report is extensive and very easy to use.
|Plagiarism checker||Plagiarism detected||Overall score|
|50% plagiarised text||100% plagiarised text|
|10. SE Reports||4%||34%|
Plagiarism checker reviews
- Best plagiarism checker on the market
- Access to scholarly databases
- Easy to use
- Plagiarism percentage + list with sources
- Trusted and used by universities worldwide
- Safe and secure
- Quality comes at a price
Scribbr is clearly the best plagiarism checker for students. Of all the plagiarism checkers we tested, this one was most successful at detecting plagiarism. Furthermore, the plagiarism report includes a clear plagiarism percentage and a list sources that have similarities with your document.
Scribbr’s plagiarism checker has the largest database of scholarly sources and is therefore capable of finding more similarities compared to other plagiarism checkers.
- Billions of web sources
- Millions of publications and scientific articles
Scribbr’s plagiarism checker can detect not only exact similarities but also patchwork plagiarism (i.e. slightly rewritten text). In addition, the technology has the options available to ignore your bibliography and properly quoted text. This results in a much more reliable plagiarism check.
The plagiarism report is clear and contains all the information you need. It reports a plagiarism percentage, a list of sources and a color-coded copy of your document that highlights areas with potential plagiarism.
Unfortunately, the Ephorus plagiarism checker is not available to students.
- Scholarly database access
- Clear plagiarism report
- Safe and secure
- Currently not available to students
The Ephorus plagiarism checker has been acquired by Turnitin. Some universities still use the Ephorus technology, but they are gradually upgrading to Turnitin.
Ephorus has access to many sources and is therefore able to detect large amounts of plagiarism.
- Ephorus database
- Internet sources
- Journal articles
The Ephorus algorithm is the second-best on the market, after Scribbr. Like Scribbr, Ephorus can detect patchwork plagiarism.
The plagiarism report is detailed and easy to read, as you can see in the example above. Plagiarized sentences are highlighted, and the source is displayed in the margin. Moreover, every source is highlighted in a different color.
Recommended: Yes, if you don’t mind a monthly subscription
Price: $9.99 per month
- Simple to use
- Free trial for three documents (max. 500 words)
- Built-in citing option
- Does not check for plagiarism against scholarly articles
- Does not find all plagiarized sentences
- Some sentences are falsely marked as plagiarism (false positives)
- No individual checks possible, only monthly subscriptions
In both documents, the Quetext plagiarism checker was able to find more plagiarized text than most other checkers.
However, it detected much less plagiarism than Scribbr. If your university uses a more advanced tool, then you might be surprised by unexpected plagiarism that Quetext didn’t find.
Quetext’s database is considerably smaller than that of Grammarly and Scribbr. It only checks for plagiarism against Internet sources and online books. It does not detect plagiarized text from journal articles.
- Internet sources
Unlike many other plagiarism checkers, Quetext is capable of detecting plagiarism, even if some words are changed. However, the algorithm does detect many false positives. This means that the reported plagiarism percentage is in fact much higher than it should be.
The results are reported in a nice overview that includes a percentage and highlights the sentences that are matched with other sources. Quetext also has a built-in citation feature to help you cite plagiarized paragraphs.
4. Compilatio Studium
Recommended: Yes, but be aware of the absence of a detailed report
Price: $5 for a 1-day package (max 7,500 words); bigger packages are available
- Rather cheap; credits bought can be used for multiple documents
- Does not report any false positives
- You can’t see what parts of the text contain plagiarism
- PayPal is the only payment method
- Does not have access to a database with student papers and theses
The Compilatio Studium plagiarism checker is of good quality and reported high plagiarism percentages for both documents. The sources found are accurate and divided into three categories: “matching similarities,” “assumed similarities” and “accidental similarities.”
However, it does not report which parts of your document are plagiarized. This makes it hard to add accurate citations or rewrite your text.
The Compilatio Studium plagiarism checker only compares your document against available Internet sources and its own database. It does not check your work against papers submitted by other students.
- Internet sources
- Own database
The algorithm finds the right source for plagiarized text. In contrast to some other plagiarism checkers, it did not report any false positives.
Unfortunately, the report is limited to a plagiarism percentage and a list of sources. An overview of where your text contains plagiarism is missing.
After doing the check, you know which sources your paper matched with but not where to put the citations. Other plagiarism checkers do have this feature.
Recommended: If you’re willing to pay for a plagiarism checker, there are better alternatives
Price: Three-day trial (credit card required) and then $10 per month (maximum of five checks)
- Three-day trial period
- Built-in citing tool
- Built-in spelling checker
- Does not provide a plagiarism percentage
- Your document is added to the BibMe plagiarism database
- Maximum five checks per month included in the price of $10
The database is small, and the matching algorithm does not perform as well as other plagiarism checkers. If you’re willing to spend money on a plagiarism checker, then there are better alternatives.
If you want to make use of the BibMe plagiarism checker, you’ll need to sign up for BibMe Plus. After the three-day trial, it costs $10 per month and includes five plagiarism checks per month.
The database includes basically everything that is openly accessible online. BibMe is able to find the plagiarized text from journal article abstracts, but not from the content of the article.
- Internet sources
The algorithm found quite some plagiarism in Document #2 (100% plagiarized text). However, it detected very little plagiarism in Document #1 (the real paper).
For students, this plagiarism checker is less suitable, as their papers often contain slightly rewritten text rather than 100% plagiarism.
BibMe does not report a plagiarism percentage as other plagiarism checkers do. It only highlights the parts of the text that are plagiarized.
BibMe does include some useful additional features, such as a spelling checker (which is of moderate quality) and a citing tool.
Recommended: Yes, if you don’t mind that some potential plagiarism is not detected
Price: Free trial (2,000 words); $9.99 for 50,000–200,000 words
- Money-back guarantee
- Relatively cheap
- Free trial for up to 2,000 words
- Did not find much plagiarism in Document #1 (real paper)
- Some text is falsely flagged as plagiarism
- No access to databases with student papers
Plagscan is a widely used plagiarism checker that performed well with Document #2 (100% plagiarized text). However, in Document #1 (real paper), which contained patchwork plagiarism, Plagscan did not detect much plagiarism. This shows the quality difference with, for instance, Scribbr.
The downside of Plagscan is the size of its database, which is smaller than that of Scribbr, Ephorus and Grammarly. Plagscan therefore cannot detect plagiarism from certain sources.
- Internet sources
The algorithm is smart enough to flag plagiarized paragraphs with some changed words. However, the algorithm sees every sentence as separate, resulting in many separate plagiarism matches with the same source.
The plagiarism report is clear and easy to use. You receive a list with all the matched sources, which are also highlighted in the document itself. In the report, the text is categorized as “exact match,” “possibly altered text” and “marked as quotation.” However, the categorization does not work perfectly.
Recommended: Yes, if you’re on a budget and do not mind spending time looking into falsely marked plagiarism.
Price: $0.35 per page
- Rather cheap at $0.35 per page
- It’s hard to recognize your own document as it removes all paragraphs (see screenshot)
- Requires an account in order to use the trial
- In order to get free credits, you need to post on social media
The Plagramme plagiarism checker found a high percentage of plagiarism in Document #2. However, it falsely flagged a lot of words and sentences. This makes the plagiarism percentage less reliable.
The pricing of the plagiarism checker is confusing. Plagramme claims to offer a free check, but in reality, it only gives you the plagiarism percentage for free. To find out which parts of the text are plagiarized, you have to buy credits.
- Internet sources
- Journal articles
The algorithm works rather well, even when some words are changed. It does flag quite a lot of false positives. Furthermore, it does not detect all plagiarism, even if the original information comes from a source that the checker has access to.
One of the shortcomings of this check is that the document doesn’t keep the original formatting (as can be seen in the screenshot).
Recommended: No, Grammarly did not detect any plagiarism in Document #1 (the real paper)
Price: $29.99 for one month (or cheaper when choosing a yearly plan)
- Combined with a world-class spelling and grammar checker
- Access to ProQuest’s database
- Fails to detect patchwork plagiarism (only detects exact similarities)
- Only available as a monthly subscription
Grammarly focuses on its spelling and grammar tool and offers the plagiarism checker as an additional service. If you’re already a paying Grammarly customer, then using their plagiarism checker might be a good option.
However, if you really want to identify plagiarism in your paper, then you are better off using another plagiarism checker that is capable of finding more than exact matches.
Grammarly’s plagiarism database is quite extensive. It can check your document against the following sources:
- ProQuest’s database
- Internet sources
- Journal articles
The Grammarly plagiarism checker does not perform well when some words in a plagiarized paragraph are changed (patchwork plagiarism). It detected 0% plagiarism in Document #1 (a real paper), whereas other plagiarism checkers like Scribbr detected 44% plagiarism.
Grammarly is easy to use. It reports a plagiarism percentage and a list of sources in which the matching text can be found. The plagiarized text is underlined in the document next to possible spelling and grammatical errors.
Recommended: No, it uses a very poor algorithm, has a small database and is not user-friendly.
- A lot of distracting ads and buttons
- 1,000-word limit
- The plagiarized text is not highlighted in the document
- Only finds exact matches with Google Search (you’ll need to find the source yourself)
- Doesn’t detect plagiarism when some words are changed
As the name suggests, Smallseotools is a free plagiarism checker primarily meant for marketers who want to check short snippets of text for plagiarism. We only reviewed Smallseotools because a lot of students use it.
Overall, this is not a good plagiarism checker for students as the results are not reliable and are very tough to analyze.
Smallseotools has no specific database. This plagiarism checker enters every sentence in Google Search to see if it finds a match. When it does, it marks the sentence as plagiarized. As can be seen in the plagiarism percentage, this method is very unreliable.
Smallseotools uses Google’s “exact search” to find matches. There is no database or advanced algorithm, which is reflected in the limited amount of plagiarism detected by the check.
The downside of the Google Search method is that you have to find the source of the matched text in the search results by yourself.
This plagiarism checker doesn’t highlight the plagiarized text in the document. It only provides you with a list of plagiarized sentences.
10. Search Engine Reports
Recommended: No, it does not find much plagiarism
Price: Free (maximum 1,000 words per check)
- Shows plagiarized text on the webpage
- Does not work for long texts (max 1,000 words per check)
- A lot of distracting ads
Just like the Smallseotools plagiarism checker, Searchenginereport.net is built for businesses rather than students.
The performance of these plagiarism checkers is similar. In Document #2 (100% plagiarized text), the checker did detect plagiarism, but it did not detect plagiarism in the real paper.
This plagiarism checker only compares your document against sources available on the Internet.
The algorithm is poor. It finds exact matches but is unable to detect plagiarism when some words are changed. Furthermore, the algorithm analyzes every sentence individually instead of analyzing the paragraph as a whole.
The report only shows a list of sentences that are possibly plagiarized. When checking a larger document, this can be confusing because every sentence is shown separately. If you want to find the source of the plagiarized text, then you are redirected to Google’s exact search.
Recommended: No, it finds very little plagiarism and possibly sells your document
Price: Free (used as marketing to acquire customers for their essay writing service)
- When using the check, you grant Edubirdie a royalty-free licence for your document
- Hard to analyze the plagiarized parts due to the small window used to display feedback
- Detects very little plagiarism
Edubirdie’s plagiarism checker is of very poor quality. It found much less plagiarism compared to other checkers. Its database is rather small, and the algorithm only checks for exact matches.
Edubirdie only checks against major Internet sources. Plagiarized text from small websites is not detected.
- Internet sources (major websites only)
The algorithm is really poor. It only finds exact matches. When a few words are changed, it does not detect any plagiarism. Furthermore, Edubirdie marks some parts of the text as plagiarism even when they aren’t plagiarized.
The window that displays the plagiarism check results is small and fairly useless for students with a large document. You can only see four to six sentences at a time.
Frequently asked questions about plagiarism
- Is it plagiarism if you cite the source?
If you correctly cite the source you do not commit plagiarism. However, the word 'correct' is vital in this sentence. In order to avoid plagiarism you must adhere to the guidelines of your citation style (e.g. APA citation style or MLA citation style).
Plagiarism checker software can be used to check your text for plagiarism. This software compares your text with billions of webpages, books and articles.
- What is the difference between plagiarism and paraphrasing?
Plagiarism is the act of using someone else’s work or ideas without crediting the original author and thereby pretending it’s your own.
Paraphrasing means rephrasing the original text in your own words.
So, where does the confusion come from?
When using someone else’s work, you can either quote or paraphrase it to prevent plagiarism. Paraphrase a text if you want to clarify or shorten the original text. Quote the text if you want to keep the exact wording and meaning of the original source.
- What happens if you plagiarize?
If you’re a student, then you might fail the course, be suspended or expelled, or be obligated to attend a workshop on plagiarism. It depends on whether it’s your first offense or whether you’ve done it before.
As an academic or professional, the consequences are more serious. Aside from the fact that plagiarizing seriously damages your reputation, you might also lose your research funding and/ or your job.
Plagiarizing is a serious offense, and knowing how to avoid plagiarism is therefore important. Read more about the consequences of plagiarism and use a plagiarism checker to detect plagiarism yourself.
- Are plagiarism checkers accurate?
The accuracy depends on the plagiarism checker you use. Scribbr is the most accurate plagiarism checker. Many free plagiarism checkers fail to detect all plagiarism or falsely flag text as plagiarism.
Take a look at this comparison of free and paid plagiarism checkers for students to find the most accurate plagiarism checker.
The accuracy is determined by two factors: the algorithm (which recognizes the plagiarism) and the size of the database (with which your document is compared).
Size of the database
Many free plagiarism checkers only check your paper against websites – not against books, journals or papers previously submitted by other students. Therefore, these plagiarism checkers are not very accurate, as they miss a lot of plagiarism.
Most plagiarism checkers are only able to detect “direct plagiarism”, or instances where the sentences are exactly the same as in the original source. However, a good plagiarism checker is also able to detect “patchwork plagiarism” (sentences where some words are changed or synonyms are used).
- Can you use Turnitin for free?
Unfortunately, as a student, you cannot use Turnitin for free. Turnitin only makes its plagiarism prevention software available to universities and other institutions. If you’re a representative of a university you can contact the sales department of Turnitin.
For students, a good alternative to Turnitin is the Scribbr Plagiarism Checker. Prices depend on the size of your document and start at $18.95.
For this price, students receive a full report that highlights the similarities in the text, displays a plagiarism percentage, and includes a list of the sources found.
- Is paraphrasing considered plagiarism?
- Can you plagiarize yourself?
Although it sounds contradictory, you can indeed plagiarize yourself. This is called self-plagiarism. Self-plagiarism goes against the expectations of the reader that the paper you submitted is new.
You can plagiarize yourself by, for instance:
- Submitting a document you previously submitted for a different course
- Using a section of a previous paper without correctly citing yourself as the source
Although self-plagiarism is often unintentional, it can have serious consequences. Be sure to cite your previous work or discuss the decision to use your old paper with your professor.
- Should I check my paper for plagiarism before submitting it to my instructor?
If you’ve correctly cited all the sources you used, then you do not need to use a plagiarism checker before submitting your paper to your instructor. However, if you want to be sure that you didn’t forget to cite anything, then you can use a plagiarism checker yourself.
To help you, we compared popular plagiarism checkers to find out which one is best.