AI Model Detector: Which Model Wrote This Text?
TheChecker.AI identifies which of 40+ AI models likely produced a text — not just that it is AI. Per-model pages for GPT-5, Claude, Gemini, Llama and Mistral.
GPT-5
Not just 'AI detected' — a per-sentence map and GPT-5 named as the likely source when it is.
Read moreClaude
Per-sentence scores plus Claude named as the likely source — and Claude itself can call the detector over MCP.
Read moreGemini
Gemini lives one click away inside Google Docs — here is how to tell when it did the writing.
Read moreLlama
The open-weights model behind a thousand product names — detected even when the app never says 'Llama'.
Read moreMistral
The French lab's open models power apps that never say 'Mistral' — attribution finds them anyway.
Read moreNot sure where to start? Paste any text and see for yourself.
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