GPTZero

GPTZero is the world's most accurate commercial AI content detector, founded in 2023 by Princeton student Edward Tian. It specializes in identifying text generated by ChatGPT, GPT-5, GPT-4, Gemini, Claude, Llama, and their derivatives, serving over 10 million users across 100+ countries with official partnerships including the American Federation of Teachers.

Powered by a proprietary 7-component AI detection model fine-tuned for student writing and academic prose, GPTZero delivers detection at document, sentence, and word levels with 99% accuracy per independent benchmarks. TechCrunch named it the "best and most reliable AI detector."

The tool is widely used in education, hiring, publishing, content platforms, and misinformation detection, supporting 17 languages with integrations for Chrome, Google Docs, Canvas, Google Classroom, Zapier, and a developer API.

AI Content Detection

Core functionality detecting content from ChatGPT, GPT-5, GPT-4, GPT-3, Gemini, Claude, Llama, and all derivative services. Provides document-level, sentence-level, and word-level precision with highlighted AI-generated segments.

Hallucination Detector

Identifies fabricated information, invented citations, and factual errors in AI-generated content, helping educators and content reviewers quickly spot AI hallucinations and improve content credibility.

Writing Report

Offers video playback to reconstruct the writing process and uses human writing verification technology to determine whether an essay was genuinely written by a human — especially valuable for academic integrity reviews.

Plagiarism Checker

Built-in plagiarism detection module works alongside AI detection to complete both checks in a single scan, saving review time for educators and publishers.

AI Tutor

Writing feedback tools for students that help improve writing quality with specific suggestions, going beyond simple "AI or not" judgments to support genuine skill development.

Batch Scanning

Free tier supports up to 150,000 characters or 250 files in batch mode. Professional and Enterprise tiers support larger-scale batch processing for schools, publishers, and enterprises.

Multi-Platform Integration

Chrome extension "Origin" for one-click full-page scanning; deep integration with Google Docs, Canvas, and Google Classroom; Zapier automation support; and API SDKs for Node.js, Python, C#, Java, and PHP.

1. Visit GPTZero and sign up with email or Google — no credit card required for the free tier.
2. Paste text or upload a PDF, Word, or TXT document in the main interface.
3. Click "Get Results" — the detection report is returned within seconds.
4. Review the report: overall AI probability score, sentence-level highlights (yellow = suspected AI), and word-level precision markers.
5. For batch detection, switch to "Batch" mode and upload up to 250 files at once.
6. For workflow integration, install the Chrome extension or connect via the API.

Industry-Leading Accuracy

99% accuracy per the latest independent benchmarks — the highest among all commercial AI detectors. TechCrunch named GPTZero the "best and most reliable AI detector," a result of its proprietary 7-component model and academic writing fine-tuning.

Built for Education

The only AI detector with an official partnership with the American Federation of Teachers, adopted by 380,000 educators. The Writing Report feature reconstructs the writing process, helping teachers distinguish genuine student work from AI-generated submissions.

Multi-Level Detection Granularity

Document, sentence, and word-level detection precisely locates every AI-generated segment rather than just providing an overall probability — critical for handling "human-AI hybrid" content.

Broad Model Coverage

Detects not just ChatGPT but GPT-5, GPT-4, Gemini, Claude, Llama, and all derivative services, with continuous updates as new models are released.

Comprehensive Ecosystem Integration

Chrome extension, Google Docs add-on, Canvas/Google Classroom integration, Zapier support, and 17-language multilingual detection allow GPTZero to fit seamlessly into existing workflows.

Pricing subject to change — see pricing page for current rates. Annual billing saves 45%. All paid plans include 17-language detection and API access.

• Help Center: gptzero.me/faq with detailed guides and FAQs
• API Documentation: gptzero.me/api for developers
• Email support: submit a ticket via the contact form on the website
• Chrome Extension: Origin by GPTZero
• Social: Twitter/X @gptzero_me for product updates

Related Tools

• GPTinf — AI text rewriter that transforms AI-generated content into more natural human-like writing, pairs well with GPTZero for detection and bypass workflows
• Winston AI — Professional AI content detector supporting multi-model detection and plagiarism scanning, one of GPTZero's primary competitors