GPTZero vs Plagiarisma
GPTZero
gptzero.mePlagiarisma
plagiarisma.netSide by side
| Figure | GPTZero | Plagiarisma |
|---|---|---|
| Price from | $8.33/mo | $8.25/mo |
| Free plan | Yes | Yes |
| Free trial | Yes | Yes |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | — | Yes |
| Android | — | Yes |
| API | Yes | Yes |
| Plans published | 4 | 8 |
| Spec score · Plagiarism Detection Software | 9.1 (#3) | 9.0 (#6) |
| Headquarters | New York, United States | 71-75 Shelton St, London WC2H 9JQ, United Kingdom |
| Intended users | GPTZero describes its audiences as educators and students, as well as publishers, recruiters, copywriters, marketers, and businesses. | The homepage describes the checker as designed for students, bloggers, and freelance writers. |
| Languages | GPTZero says it fully supports English, German, Portuguese, French, and Spanish. | The homepage says the checker supports more than 190 languages. |
| Purpose | GPTZero identifies AI-generated text and highlights AI use at document, sentence, and word level. | The online checker scans text against web sources, books, and academic papers for originality. |
| Support | The site directs users to its Support Center and customer service team for help. | The contact page lists [email protected] and says premium members should include a valid order ID when reporting issues or sending suggestions. |
| What it does | GPTZero detects likely AI-generated writing and identifies AI use at document, sentence, and word level. | Plagiarisma checks pasted text, uploaded documents, and URLs for matching passages and reports a uniqueness score. |
Plans
GPTZero
- FreeFree
- Essential$8.33 a month
- Premium$12.99 a month
- Professional$24.99 a month
Plagiarisma
- Plagiarisma Desktop Plagiarism CheckerFree
- Standard checksFree
- One-day subscription$2, paid once
- One-month subscription$10, paid once
- Three-month subscription$25, paid once
- Six-month subscription$49, paid once
- One-year subscription$99 a year
- Paid featuresPrice not published
In their own words
GPTZero
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.
Plagiarisma
Plagiarisma is an originality checker that compares text with web sources, books and academic papers. Users can paste text, enter a URL or upload a document in formats including PDF, DOCX, RTF, TXT, HTML, spreadsheets, presentations and ebooks. Its homepage says the checker supports more than 190 languages. The service runs on the web and has a Windows desktop download listed as version 2.0 for.NET on Windows x86/x64. Desktop tools include plagiarism scanning, AI content detection, paraphrasing and APA citation generation. A Google Docs add-on offers checking, paraphrasing, summarizing and AI detection; its listing allows five free document scans per day, with paid features available by monthly subscription. A free plan is listed, including a Windows desktop checker at free. The company says it does not store private texts in public databases. Its FAQ says premium membership orders may be refunded within three days, while trial orders are not refundable.