Plagiarism Checker X is a desktop application for Windows that detects content similarity and plagiarism in documents. It scans text against billions of web pages and can compare documents against each other. Files stay on the user’s computer instead of being uploaded to an external database, which the company emphasizes as a privacy point.
Its AI feature is an AI Content Detector, which gives an indication of whether content was produced by an AI tool or written by a human. It complements the plagiarism scan: the software detects, and does not rewrite text to avoid detection. The company cites use in more than 120 countries and an office in New York City.
A free download has limited functionality, and the Pro version is listed at $39.95. The company does not say on its homepage whether that is a one-time or recurring charge, so confirm the terms before buying. As with any AI detector, the result is an indication, not proof of authorship.






