Detecting-AI.com vs GPTZero

Detecting-AI.com analyzes writing for signals associated with AI-generated text and presents a document score with highlighted passages. The web detector accepts pasted text plus TXT, PDF, and DOCX files; scanned PDFs requiring OCR are not supported. It is designed for text linked to GPT, Claude, and Gemini, including edited or AI-assisted drafts. The service preserves document structure, scores eligible sentences separately, and combines those scores into a document signal. The maker reports 99% detection accuracy and a false-positive rate under 1% on its described datasets, while noting that short, translated, heavily edited, or formulaic writing can be harder to classify and that a score cannot establish authorship or misconduct. Paid plans add unlimited AI detection, an AI Humanizer, Fact Checker, and plagiarism credits. REST APIs cover detection, humanization, and plagiarism checks, with a remote MCP server for compatible assistants. The free plan requires no account and allows 15,000 characters per check. Paid pricing starts at $7 a month billed annually.

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.