GPTZero review: our take
GPTZero is the detector most built around the classroom. The free scanner takes up to 10,000 characters, and the Chrome extension and Canvas and Google Classroom integrations put checks where teachers already work. Writing Replay is the most useful part: it shows how a document was typed, which says more about process than any percentage.
Premium costs $12.99 a month and Professional $24.99, both billed yearly. GPTZero claims 99% accuracy and a 1% false positive rate on ESL writing, but independent studies have found detectors misclassify non-native English writing, so treat a score as a reason to talk to the writer. Our AI detectors guide covers that research. For a lower vendor-claimed false positive rate, compare Pangram; for publishers, Originality.ai.
By the Prompt Hackers team · facts checked 4 Oct 2026
What GPTZero does
GPTZero estimates whether a text was written by a person, an AI model or a mix of both, and highlights the passages behind the score. Around the detector it offers a plagiarism checker, a hallucination detector, Writing Replay that shows how a document was typed, a Chrome extension for Google Docs and Classroom, and integrations with Canvas and Google Classroom.
Who GPTZero is for
Best for
- teachers who want scans inside Google Docs and Classroom
- editors triaging submissions before a closer read
Not for
- grading or discipline on a score alone: GPTZero says its false positive rate on ESL writing is trained toward 1%, so some human writing will still be flagged
- short or non-English text: GPTZero notes detection is strongest on longer English prose
GPTZero features
- F1AI detection with sentence highlights
- F2Mixed human and AI document detection
- F3Writing Replay
- F4Plagiarism Checker
- F5Hallucination Detector
- F6Chrome extension
- Google Docs, Gmail, Classroom
- F7Canvas and Google Classroom integrations
- F8API
GPTZero pricing and plans
| Plan | Monthly | Billed yearly, per month | What it includes |
|---|---|---|---|
| Free | $0 | — | scans up to 10,000 characters; longer scans need a free account |
| Premium | — | $12.99 | up to 300,000 words a month, multilingual detection, downloadable reports |
| Professional | — | $24.99 | up to 500,000 words a month, batch scans of up to 250 files, LMS integration |
| Teams and Enterprise | — | — | contact sales; shared team credits and unified billing |
Free plan: yes. Prices as listed by the vendor in USD, before tax; they change, so check the pricing page before you buy.
GPTZero FAQ
- Does GPTZero have a free plan?
- Yes, GPTZero has a free plan.
- What are the alternatives to GPTZero?
- Tools that cover the same jobs include Pangram, Originality.ai, Turnitin, Grammarly.