Turnitin and iThenticate Similarity Detection

Turnitin and iThenticate are commercial text-matching software tools used by educational institutions and academic journals to screen submissions for potential plagiarism. Turnitin is designed for student assignments; iThenticate is designed for researcher manuscripts. Both tools compare submitted text against billions of sources (web pages, academic databases, previously submitted documents) and generate a Similarity Index showing what percentage of the submission matches existing sources. These tools are screening instruments, not plagiarism detectors—they flag suspicious content for human review.