I have just tested two plagiarism checkers. http://smallseotools.com/plagiarism-checker/ and http://plagiarisma.net/. I used this text to test them: “Of the gracious Doctor Gregory of Narek, which he wrote to the celebrated convent of Kdjav, concerning the tenets of the cursed Thonraki, lanes and Iamres, who came in the guise of sheep, but within is a ravening wolf; who moreover by his fruits was made known to all. Him the holy doctor having heard of, wrote in order to liberate others from the evil tenets.” It is part of The Letter of St. Gregory of Narek translated by Frederick Cornwallis Conybeare. Both of them were wrong and claimed that my piece was 100% unique. This surprised me. I tried one more http://www.plagtracker.com/, which claims to be “The Most Accurate Plagiarism Checking Service”. It came back with a correct 100% non-unique result.

For me this is one is a no-brainer. It’s PlagTracker all the way.