Most free AI detectors stop at a few hundred or a few thousand words. PaperCheck checks a whole thesis or project report, up to 20,000 words per check, from a Word or PDF file, and marks the exact lines that read as AI.
Written by Adithyan, a student who builds PaperCheck. Last updated 22 October 2026.
AI-like writing usually sits in a few places: the introduction, the literature review, the conclusion. Checking random pieces can miss them. Checking the whole file shows where they are.
The title page, certificate, declaration, acknowledgement, table of contents, tables, lists and references are skipped, so they do not change your score.
The text is scored in 250-word sections, similar to how Turnitin reports AI writing, and the score is the share of words in sections that read as AI.
Yes. Each free check covers up to 20,000 words, and you get 5 a month.
Yes, Word (.docx) and PDF both work.
Check your paper: 5 free checks a month
PaperCheck is not affiliated with Turnitin, GPTZero or Pangram. Scores from any detector are estimates, not proof.