DrillBit and Turnitin compare your thesis against different collections of web pages, journals and student papers, so the same file can get different similarity scores. Neither number is wrong; they measured against different sources.
Written by Adithyan, a student who builds PaperCheck. Last updated 31 October 2026.
DrillBit is an Indian plagiarism checker used by many Indian universities. Turnitin is an international checker that also gives an AI-writing score. Your university decides which one it uses, and some use both.
Each tool has its own database, its own rules for what counts as a match, and its own settings for excluding quotes and references. A phrase found in one database may be missing from the other.
PaperCheck checks plagiarism against the papers you cite plus arXiv, Wikipedia, Europe PMC and OpenAlex, and gives an AI-writing score. It does not search DrillBit's or Turnitin's databases, so use it to fix problems early, not to predict an exact number.
Neither is simply stricter; they search different sources, so the score depends on where similar text exists.
Check your university's report. Turnitin reports an AI-writing score; tools differ in what they include.
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PaperCheck is not affiliated with Turnitin, GPTZero, papercheck.in or papercheck.ai. Scores from any detector are estimates, not proof.