GPTZero

What it does

GPTZero is a free AI checker that analyses text to identify whether it was written by a human or generated by AI models such as ChatGPT, GPT-4, Gemini or LLaMa. It uses a deep analysing algorithm to spot AI patterns and writing tone, and gives sentence by sentence results. It is aimed at content creators, academic and research institutions, work teams, SEO specialists and general users.

GPTZero is a web tool for checking whether a piece of text looks AI generated. You type, paste or upload a file, then click Detect Origin. The tool returns a prediction and a sentence by sentence analysis. The free plan allows 3,000 characters per scan. The Pro plan raises this to 10,000 characters and removes ads. The site says it supports English and French. It also says accuracy varies between detectors and that some AI text can be paraphrased or humanized to evade detection. Treat the result as a signal, not proof. The site does not publish accuracy figures or independent validation.