GPTZero

GPTZero is an AI detection platform that uses a combination of perplexity and burstiness analysis — statistical measures of text predictability and variation — to assess the likelihood that a piece of writing was produced by an AI language model rather than a human author. The tool returns a probability score for the full document along with sentence-level highlighting that identifies specific passages most likely to be AI-generated. This granular breakdown is useful for reviewers who need to understand which sections of a document require closer scrutiny rather than simply receiving a binary pass or fail result. The free plan provides 10,000 words per month of basic AI scanning with three Advanced Scans included. See similar solutions. GPTZero's primary user base consists of educators and academic institutions screening student submissions for AI-generated content, alongside publishers, HR teams, and content operations that verify the originality of written work before approval or publication. The Premium plan at $12.99 per month billed annually — or $23.99 month-to-month — covers 300,000 words per month with full Advanced AI Scan access, multilingual detection, and downloadable reports. The Professional plan at $24.99 per month annually — $45.99 monthly — adds up to 500,000 words per month, batch scanning of up to 250 files simultaneously, page-by-page scanning for longer documents, overage capacity up to 10 million words, and enterprise-grade security with LMS integration for institutional deployment Read our guide.