What this tool checks
The checker scans for zero-width spaces, joiners, byte-order marks, soft hyphens, and non-breaking spaces. These characters can cause formatting, linting, search indexing, or copy/paste problems, especially in code, docs, CMS editors, and shared drafts.
What Anthropic says
Anthropic's support article says compatible Claude models weave an imperceptible watermark directly into generated text. It also says a detected mark is a signal that content may have been processed by Claude, and that detection details will be shared in forthcoming technical documentation.
FAQ
What does this Claude watermark remover clean?
It cleans common invisible Unicode characters and formatting artifacts that can travel with copied AI text. As Anthropic releases more detection details, provider-specific checks can be added.
Does Anthropic say Claude uses zero-width spaces as the watermark?
The cited Anthropic article confirms embedded text watermarks, but it does not identify zero-width spaces, em dashes, or visible style habits as the watermarking mechanism.
Is the text uploaded?
No. The checker runs in the browser and does not send pasted text to a server.