GPTZero

What is GPTZero?

GPTZero is an AI text detection and writing-authorship analysis platform. Its primary purpose is to estimate whether a document was written by a person, generated by an AI system, or produced through a mixture of human and AI writing.

The service is aimed at people who need to assess document authenticity rather than generate content. It can analyze pasted text and supported uploads such as DOCX, PDF, and image files, then return document-level and sentence-level findings. The results are intended as evidence for review, not as a definitive verdict about who wrote a document.

What GPTZero actually does

The main workflow is straightforward: a user submits text or a document, runs a scan, and reviews highlighted passages and classification information. GPTZero can identify likely AI-written sections within a document and distinguish mixed documents that contain both human and AI-generated material.

Advanced scanning features provide explanations of stylistic or rhetorical patterns associated with AI-like writing. Depending on the workflow and plan, users can also access plagiarism-related checks, citation and hallucination checks, and writing feedback. These tools supplement the central detection function rather than turning GPTZero into a general-purpose writing assistant.

Writing Replay and authorship evidence

GPTZero’s main distinction from a basic AI detector is its focus on the writing process. Writing Replay can show revisions, pastes, typing patterns, and writing sessions when the document was created or captured through GPTZero’s editor, Google Docs revision history, the Chrome extension, or another supported integration.

This matters in settings such as education or professional review, where the question is not only whether the final text resembles AI output but also whether there is evidence of drafting and revision. Writing Replay cannot reconstruct the complete history of every existing file after the fact. The relevant activity must have been recorded through a supported editor or integration.

How people use GPTZero

• Education: Teachers and institutions can review essays, reports, and other assignments for likely AI-generated passages, while using writing-process evidence as additional context.
• Writing and publishing: Writers, editors, and publishers can screen submissions or inspect whether a document contains mixed human and AI writing.
• Recruiting and professional review: Organizations can use document analysis as one input when evaluating the authenticity of written work.
• Software integrations: Developers and institutions can connect detection workflows through the API or supported education integrations.

GPTZero is therefore closer to an authorship and document-review tool than to a chatbot such as ChatGPT, Claude, or Google Gemini. It does not primarily help users brainstorm, answer questions, or create content; it evaluates text that already exists and, in some workflows, the process behind that text.

Platforms and integrations

The core product is available through the GPTZero website. A Chrome extension supports Google Docs and other supported web-based writing environments, including Canvas, Notion, Substack, and Medium. GPTZero also documents institutional integrations with Canvas and Blackboard, as well as API access for organizations that want to add AI-content analysis to their own applications.

These integrations are particularly important for authorship review because they can provide access to document history or allow detection to be placed inside an existing education or publishing workflow. The browser extension and integrations do not mean that GPTZero can recover writing history from any document; capture depends on the supported environment and how the document was created.

Access and pricing

GPTZero offers continuing free general use. Free and paid plans support the main detection workflow, while paid subscriptions increase character limits, batch-upload capacity, and provide education-oriented settings and thresholds. Text longer than 10,000 characters requires a free account according to the product information.

Subscription pricing is offered through monthly and annual billing, but current public plan prices were not verifiable without entering the account-based subscription flow. API access is separate from ordinary dashboard subscriptions. GPTZero’s support documentation states that API overages are charged at $0.00046 per word and may be limited to one million additional words before an upgrade is requested. Enterprise and institutional access is available, although exact pricing and contract terms depend on the organization.

Privacy and data considerations

Data handling differs between the dashboard and API. GPTZero’s API documentation states that submitted text and files are not stored by default. The privacy materials indicate that dashboard submissions may be retained and that dashboard input may be used in aggregate to improve the service, subject to the applicable policies and account arrangement.

Organizations reviewing student, employee, or client documents should examine the current privacy policy and product-specific terms before uploading sensitive material. GPTZero states that users retain ownership of submitted work, but retention and processing can vary by product surface. Its privacy materials also describe safeguards and compliance considerations related to SOC 2 Type II, FERPA, GDPR, and CCPA, while noting that no internet transmission or storage system can be guaranteed completely secure.

Important limitations

• Detection is probabilistic: A positive result is not conclusive proof that a person used AI, and a negative result does not prove that writing is entirely human-authored.
• Accuracy varies by text: Results are generally more useful for longer English prose than for short, heavily edited, multilingual, or unusual writing. GPTZero explicitly describes full support for English, German, Portuguese, French, and Spanish, while other languages may be less consistent.
• Writing history is not automatic: Writing Replay depends on activity being captured through GPTZero, Google Docs, or a supported integration.
• Plan limits matter: Character limits, batch capacity, education settings, and API allowances vary by subscription.
• It is not a general writing tool: Although the platform includes some writing feedback and related checks, it is not designed to replace a general writing assistant or research workspace such as Grammarly.

Is GPTZero a good fit?

GPTZero is a reasonable fit for educators and institutions that need a structured way to review student writing, especially when document history can be captured. It can also suit publishers, recruiters, and organizations that need a first-pass authenticity signal or an API-based screening workflow.

It is less suitable for users seeking an unquestionable authorship determination, for multilingual or very short text where detection may be less reliable, or for anyone looking for content generation and broad AI assistance. The strongest workflow combines GPTZero’s scan with the document’s context, the author’s explanation, revision history, and other human review.