GPTZero

GPTZero is an AI Content Detector platform that scans text and documents to identify passages generated by large language models. Founded in January 2023 and self-reporting over 10 million users, the tool has positioned itself primarily for the education sector, with native integrations for Canvas and Google Classroom forming the backbone of its institutional product.

How It Works

The core workflow is straightforward: users paste raw text or upload a document and initiate a scan. The tool returns a document-level probability score alongside sentence-level highlights that flag specific passages likely produced by an LLM. According to vendor documentation, GPTZero is designed to work across a broad range of models, including ChatGPT, GPT-4, GPT-3, GPT-5, Gemini, Claude, Llama, and Deepseek, as well as services built on those models.

For scans under 10,000 characters, the tool is accessible without an account. Longer documents and institutional features require registration or a paid subscription.

API and Developer Integration

GPTZero exposes a REST API that accepts text via POST to its v2 prediction endpoint and returns a structured detection result. The vendor provides ready-to-use code samples in 17 programming languages — Python, Node.JS, C#, Java, PHP, and others — aimed at helping teams embed AI detection into custom platforms and internal workflows.

For organizations that prefer no-code automation, the Zapier integration connects GPTZero to thousands of third-party applications. This allows teams to trigger AI detection scans automatically when new content arrives in forms, email inboxes, cloud storage, or collaboration tools, without writing any integration code.

Education Integrations

The Canvas LMS integration is a flagship feature. Once configured, detection results appear directly inside SpeedGrader and standard assignment views, so educators can review AI probability scores and sentence-level highlights without switching between tools. The Google Classroom integration extends this with rubric support: instructors can upload custom rubrics and receive AI detection feedback tailored to their course's specific learning objectives and grading criteria.

Chrome Extension and Writing Authenticity

GPTZero's Chrome extension brings detection capabilities to Google Docs, bundling AI content checking with plagiarism detection and writing-effort evaluation in a single comprehensive report. A notable feature is the writing replay: the extension records the document's edit history and plays it back as a time-lapse of the writing process, showing collaborators, major revisions, and the sequence of edits. The vendor describes this as giving reviewers the experience of watching the writer write.

Pricing and Access

Basic scans are available for free. Canvas integrations and institutional features are included in GPTZero's institutional and enterprise plans. The vendor characterizes pricing as "simple and scalable," though specific plan details and per-seat costs are not publicly disclosed in the available documentation.

Academic and Research Support

GPTZero offers dedicated support channels and API access for academics and researchers, reinforcing its primary focus on the education market. This includes documentation tailored to research use cases and priority assistance for institutional users.