Writer.com has a free AI content detector tool which can be accessed on their website. It’s pretty good at detecting whether content was written by an AI, although it sometimes struggles with newer AI text generation models such as ChatGPT and GPT-3. If you use this tool in combination with another AI content detector, such as OriginalityAI, you can get a close to 100% accurate result on whether your content is likely to be detected as AI generated.
