Comparison
| Tool | Price from | Free plan | Category |
|---|---|---|---|
 Winston AI | 9 USD/mo | trial | AI detectors |
 GPTZero | not listed | yes | AI detectors |
 Turnitin | not listed | ? | AI detectors |
 Pangram | 20 USD/mo | trial | AI detectors |
 Undetectable AI | 5.00 USD/mo | trial | AI detectors |
 Originality.ai | 12.95 USD/mo | yes | AI detectors |
 ZeroGPT | not listed | yes | AI detectors |
 AI or Not | 5 USD/mo | yes | AI detectors |
Each alternative in short
1. GPTZero
Free AI detector that scores text for AI-generated content, sentence by sentence, for educators, students and writers.
Yes, there is a free plan. Free basic AI detection by pasting text into the scanner; the homepage advertises it as free. Paid features are not detailed in the provided text.
2. Turnitin
Academic integrity platform that detects plagiarism and AI-generated writing and supports grading and feedback for schools and universities.
The vendor does not state this clearly on the homepage or pricing page.
3. Pangram
AI detector that flags text and images likely generated by ChatGPT, Claude, Gemini and other models, for educators, publishers and organizations.
There is a free trial. Free tier with limited free scans (3 image scans per day shown); the Individual plan starts with a 7-day free trial.
4. Undetectable AI
Detects AI-generated text and images and rewrites AI writing so it reads as human, for students, writers and professionals.
There is a free trial. Free trial limited to 250 words; additional usage requires a paid plan.
5. Originality.ai
AI detector and content checker that flags AI-generated text and plagiarism for writers, editors, teachers and publishers.
Yes, there is a free plan. Basic plan with AI detection only: 3 scans per day, limit of 2,000 words per scan, file upload (docx, pdf, doc). No subscription required.
6. ZeroGPT
Online AI content detector that flags AI-written text and images, plus paraphrasing, grammar and plagiarism tools for writers, students and educators.
Yes, there is a free plan. Free plan, no credit card needed, with limited access to the tools (the 15,000-character limit shown on the homepage applies to the detector input).
7. AI or Not
Detects AI-generated text, images, music, video and deepfakes, for individuals and businesses via web or API.
Yes, there is a free plan. 5 USD in free credits, 1M words of AI text detection per month, 20 AI image checks and an API key included.
FAQ
What is the best alternative to Winston AI?
The most popular option in the same category is GPTZero. See the comparison table above.