There is a software named ‘Turnitin’ and other soft wares that brings out the originality reports and then that reports get interpreted by the person on the basis of the importance of the findings.
It has to be noted that in order to bring the originality reports, one has to remove the annotated bibliography, quoted material and other small matches. It is one of the trickiest task to interpret the originality of the reports and it relies on the expertise of the team member. Since, it is not wiser to blindly rely on the percentage of the similarity index and there must be a human intervention.
The safe percentage depends and differ from one university to the other. However below 25% is considered to be the safe similarity index. However, one has to be aware of the fact that there is a difference between the similarity index and plagiarism.
There are few other soft wares that are used to calculate the plagiarism are:-
Plagscan- Plagiarism Checker
Turnitin
Ithenticate
Writecheck
Unplag
Plagiarism checker
These are the probable soft wares that are used in the checking of the plagiarism. Plagiarism is the academic misconduct and therefore, use of the soft wares to detect the plagiarism are of much use nowadays.

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