GPTZero
The most-used AI writing detector in education, with sentence-level highlighting.
Visit GPTZero Free 10,000 words/mo; Essential from $10/mo
What is GPTZero?
GPTZero detects AI-generated text and highlights which sentences are most likely machine-written, with plagiarism checking and a writing-report feature that shows a document's edit history. It is widely used in schools and by editors, and is honest that no detector is perfect.
Key features
- Sentence-level AI probability highlighting
- Plagiarism scanning alongside AI detection
- Writing Reports showing how a document was written over time
- Chrome extension and Google Docs, Canvas, and Moodle integrations
- API for platforms
Pros
- Sentence-level view is more useful than a single score
- Writing Reports offer real evidence beyond probability
- Transparent about false-positive rates
Cons
- False positives remain a real risk, especially for non-native writers
- Humanised AI text often passes
- Word limits on lower tiers
Best for
Teachers who need evidence rather than a verdictEditors screening submissionsPublishers checking freelance copy
Read more
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