Is there a service which allows you to check if a paper/article was plagiarized?

At this moment, I use Google to check if some papers are plagiarized or not, but I think that are other smarter methods

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    Are you a professor? What's the context for this question? Jun 3, 2012 at 12:14
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    I'm not sure this is a writing question. Thoughts, people?
    – Standback
    Jun 3, 2012 at 13:32
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    @Standback I vote for "on topic". A proper answer could provide advice on avoiding "accidental" or otherwise unintentional or misconceived plagiarism (improperly citing a source or using a phrase that appears in another written work. And as a professor (if the OP is indeed a professor), one of his jobs is critiquing the writings of others, and part of that critique is ensuring the proper use of citations and ensuring that all uncited written work is original content.
    – Jed Oliver
    Jun 3, 2012 at 15:02
  • I agree with Jed, this is on-topic - I see it as a tools question. Jun 3, 2012 at 15:28
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    The question is, why didn't he use Google to search for a smarter method? And if he did, what's wrong with the options he found? Jun 5, 2012 at 10:55

4 Answers 4


There are many software options available (see Wikipedia's page on plagiarism detection), some free, and some paid.

To my knowledge, one of the most commonly used commercial options available is Turnitin; there is also Turnitin's student version, WriteCheck. Another commercial option is PlagScan. These options can be somewhat expensive though; PlagScan, for example, charges by the word: $13 gets you 50,000 words of plagiarism checking.

There are several free services, but they should be used with caution and their limitations should be understood. Some, for example, simply do what you've been doing: they take the sentences and search in Google. This "direct plagiarism" is much easier for the software to look for. Others, like the Viper plagiarism-scanner, do a pretty good job in my experience (from a long time ago), but still only match direct matches, and won't catch things where a word or two have been changed here or there. I've since stopped using them because they have a somewhat sketchy data retention and policy: whatever you upload, they add your work to their "study site" (or essay mill or whatever you want to call it). (To Viper's credit, they are transparent about how they use your data!)

IMPORTANT NOTE: The bottom line with free is that unfortunately you need to be very careful with them--be sure you closely read their privacy policies and their data retention policies. Commercial services may also retain your data, but generally offer an option to purge your account; nevertheless, it never hurts to read the terms of use and other relevant documents, particularly in cases of sensitive information.

If you are checking against a known local database of documents (which it doesn't sound like you're doing, but I thought I'd mention it), you can check out WCopyfind. It might not be the most intuitive, but it is promising and free. You might use this software, for example, if you have a database of papers students have submitted in the same course offered in different years, to check whether a student in the current batch of students is plagiarizing from an earlier student or from someone else in their class.


When reading a plagiarized research paper turned in by a student, the signs of plagiarism may not always be obvious. However, there are some things that professors can pay special attention to when suspecting plagiarism.

Observe citations throughout the paper: This will help determine whether or not the required citation style was used. For example, if the citations in the paper conform to Turabian style when the MLA style was required for the paper, you may be looking at a plagiarized paper.

Observe the writing style or styles used in the paper: Sometimes, you may notice that some of the writing used in a paper does not "sound like" something the student would write . The unusual words or wording may include "jargon or advanced vocabulary". Other papers may include a writing style that is below average.

Look for signs that the paper is outdated: Sometimes, professors can find signs that the paper being read may be outdated. If all of the sources listed in references or works cited are several years old, then the paper may be an example of plagiarism .

Observe the font used in the paper: A paper may contain more than one "font style or size." Different fonts throughout a paper would indicate that a student may have copied and pasted various portions of Web pages together into a word processor.


PaperRater is very good plagiarize checker. I am using this from past 2 years. Because I am taking help from the on-line sites to complete my tasks. So I am verifying the quality of content by this type of techniques. The site is very easy and also free.


There are a lot of plagiarism checkers and they show the score system. If you would get a 50% then this is totally plagiarized. 5-15% is the best what you can get as I tried some of student's papers here.

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