GPTKit vs GPTZero

GPTKit analyzes submitted text and classifies it as human-written or ChatGPT-generated. It is available through a web interface and an API, with English currently supported. The maker says the detector combines six AI-based methods, was trained on 1 million datasets, and produces authenticity and reality reports. GPTKit reports approximately 93% accuracy based on testing 100K+ human and ChatGPT responses. The first 2048 characters of every request are free, including for guests; the Free Plan allows up to five requests per minute. Unlimited (Personal) costs $5 a month and supports two team members. Unlimited (Team) costs $10 a month, supports eight members, and includes API access. Unlimited (Institution) costs $20 a month, supports 20 members, and includes API access. Team credits can be shared. GPTKit says submitted text is temporarily stored and removed after detection; its policy says absolute security cannot be guaranteed.

GPTZero identifies likely AI-generated writing and highlights detected AI use at document, sentence, and word level. Its detector can classify text as human, AI, or mixed, and provides confidence scores, explanations, AI vocabulary, and sentence-by-sentence highlighting. Advanced Scan points to passages contributing most to an AI classification. Users can submit pasted text or DOCX, PDF, and image files; the technology page says it can analyze up to 50 files at a time. GPTZero lists support for English, German, Portuguese, French, and Spanish, and detector coverage for text from ChatGPT, GPT-3 through GPT-6, Gemini, Claude, Copilot, and other models. Additional tools include Writing Replay, plagiarism checking, writing feedback, and grammar checking. The Chrome extension scans webpages and Google Docs, and integrations include Google Classroom, Canvas, an API, and Zapier. GPTZero says its results may be wrong, perform better on longer English prose, and should not be used alone to punish students. The free plan costs nothing. Paid plans start at $8.33 a month when billed annually.