Claude watermark guide
Claude Watermark Checker
A third-party Claude watermark checker can inspect hidden Unicode, unusual whitespace, and supplied file metadata. It cannot honestly verify Anthropic’s model-level statistical watermark until the appropriate public detector is available.
What this checker can inspect
This tool lists deterministic text-layer artifacts by code point and position. Those findings are observable and can be reviewed before cleaning.
What a clean result means
A clean Unicode result means no supported inspectable characters were found. It does not prove that a statistical provenance signal is absent.
Check your Claude text
Inspect every detectable hidden character locally, then clean only the artifacts you select.
Check Text FreeSources
Published August 2026 · Updated September 1, 2026