Turnitin - Turnitin is preferred by educational institutions around the world for preventing plagiarism. Instructors at all levels of education can request that students use the service to submit papers, and Turnitin checks those papers for plagiarism.
PlagiarismSearch - PlagiarismSearch is online service that detects plagiarized content.
Unicheck - The plagiarism checker Unplag scans across the internet, repositories, open sources content and databases. It delivers real-time results and has no cached data.
PlagScan - The Internet makes plagiarism a bigger problem than ever.
Urkund - Detect and check for plagiarism with URKUND
Plagiarisma - Plagiarisma.Net is a free online plagiarism checker and duplicate content finder.