| Product | GPT Version | Description |
| HuggingFace GPT-2 Output Detector | 2 | Based on the GPT-2 output detector model from OpenAI |
| Writer AI Content Detector | Unknown | Designed to help with search engine page ranking and avoiding content that is flagged if it reads like it was entirely produced by AI. |
| GPTZero | 3 | GPTZero turns the very technologies used to build ChatGPT around — to detect AI. It uses variables like perplexity to fingerprint AI involvement. Stay updated on the upcoming innovations in GPTZero technology via this substack. |