Scribbr is a popular tool for detecting AI-generated content, which includes texts produced by ChatGPT, Gemini, and Copilot. It is extremely accurate and free to use, with no registration required. The tool can detect GPT2, GPT3, and GPT3.5 with average accuracy, whereas the Premium AI Detector is more accurate and can detect GPT4. It can detect most texts produced by popular tools such as ChatGPT and Bard, but it cannot guarantee complete accuracy. The AI score is a percentage ranging from 0 to 100% that indicates the likelihood that a text was generated by AI. Accuracy Test: Scribbr’s free AI Detector received an overall score of 78%, placing it among the most accurate free tools available. It accurately detected all GPT-3.5 and GPT-4 texts and did not misidentify any human-written text as AI-generated. It also outperformed expectations when detecting AI content that had been combined with human-written text or altered using paraphrasing tools.