Claude Watermark

Paste any text and see every trace a chat interface left in it: hidden HTML class names, zero-width characters, exotic spaces, typography. Each finding has a count and a position, because these are facts about the bytes, not a probability score. Clean it in one click. Free, unlimited, no account, runs in your browser so nothing is uploaded. It does not claim to detect Anthropic's statistical watermark, because nobody outside Anthropic can. The engine is MIT open source.