Claude watermark guide
Hidden Characters in Claude Text
Text copied from Claude can be inspected for hidden Unicode such as zero-width spaces, word joiners, bidi controls, and unusual whitespace. Those characters are not Anthropic’s official statistical text watermark.
Why inspect them
Hidden controls can affect search, rendering, security reviews, and text comparison. Exact code points make a finding reproducible.
How to clean safely
Review each result, preserve normal line breaks where needed, and copy the preview only after checking it.
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