LLM tools

Private browser tool

Remove hidden marks from AI text

Paste Claude or other LLM output. Supported, structurally detectable C2PA text forms are removed as it lands. Additional hidden formatting cleanup is opt-in—no clean button, upload, or account.

The important distinction

What this tool can—and cannot—remove

It does remove

C2PA-identified Unicode wrappers, conservative edge/front-matter manifest references, and recognized C2PA associations in an explicit HTML head. When you opt in, it can also remove selected hidden formatting characters such as zero-width spaces, zero-width no-break spaces, soft hyphens, and non-emoji tags.

It cannot promise

Removal of Claude's new model-level text watermark. Anthropic has announced the mark, but has not yet published its detection algorithm. A result with no removable payload is not proof that text was written by a human or that every possible watermark is gone. Removing an embedded association also cannot prove that a durable Content Credential is undiscoverable through another binding.

Research, updated 11 August 2026

Can this remove Claude AI watermarks?

Not reliably—not yet. Anthropic says supported Claude models launched on or after 2 August 2026 weave an imperceptible watermark into generated text at the model level. The company says the signal travels through copy and paste and may survive some editing, but its technical detection documentation is still forthcoming. That description does not establish that Claude hides a C2PA block or zero-width characters inside every response.

Anthropic separately describes signed C2PA provenance metadata for supported generated files such as PNG, JPG, and SVG. That file-attached metadata is different from its embedded text watermark. When you copy ordinary rendered text from a file into a text box, the file container and its binary metadata do not come along for the ride.

What C2PA text metadata looks like

C2PA 2.4 defines an under-review method for provenance in plain text. It starts with a zero-width no-break space, then encodes a wrapper whose first bytes spell C2PATXT\0 using Unicode variation selectors. The standard also defines visible manifest blocks for structured text and dedicated script or link associations for raw HTML. This cleaner conservatively checks beginning/end comment associations, front matter, explicit HTML heads, plus the wrapper header and outer JUMBF C2PA identity before reporting a C2PA-identified Unicode wrapper. It does not fully validate the manifest or its signature, or delete every invisible character indiscriminately.

That restraint matters. Zero-width joiners and non-joiners can be meaningful in Persian, Arabic, Indic scripts, and emoji. Variation selectors can choose emoji presentation or a specific CJK glyph. Those characters are preserved unless they are part of a recognized C2PA wrapper. Recognized emoji flag tag sequences are preserved too.

How to clean pasted LLM text online

  1. Tap the text area and paste the content. Recognized C2PA cleaning happens synchronously as part of the paste.
  2. Only if needed, enable hidden formatting cleanup and review its warning before copying.
  3. Review the category-level removal summary. “No removable payload found” is intentionally not a provenance claim.
  4. Tap Copy cleaned text. The copy call starts directly from your tap for mobile Safari compatibility.

Cleaning is local to this browser tab. This tool makes no network request with your text, stores no text on a server, and records no analytics event containing the pasted content. Spellcheck and autocorrect are disabled on the field; your browser, keyboard, or extensions may still have their own privacy settings. Closing or refreshing the page clears the working text.

Why the claim is deliberately narrow

“AI watermark” can mean cryptographic file provenance, invisible Unicode, or a statistical pattern in a model's token choices. Those mechanisms are not interchangeable. Heavy rewriting, paraphrasing, or translation may change statistical signals, but it also changes the writing and is outside this narrow, visible-prose-preserving default pass. Legal and disclosure duties vary by jurisdiction and use; this utility is a text-sanitization tool, not legal advice or a provenance certificate.

Does the cleaner rewrite the visible text?

The default pass does not paraphrase sentences, normalize spelling, replace punctuation, or change letterforms. Ordinary newlines, tabs, emoji, accents, and non-Latin scripts stay intact. The optional hidden-formatting pass can change hyphenation, line breaking, or hidden tag data, so it starts off and carries an explicit warning. Exact C2PA removal remains active either way.

Primary sources