Which Claude models are affected?

Claude Opus 5: confirmed watermarking. Claude Sonnet 5: confirmed watermarking. Claude Fable 5: confirmed watermarking. Claude Haiku 4.5: likely watermarked. Claude Opus 4.8: likely watermarked. Claude Sonnet 4.6: likely watermarked. Claude Code output: confirmed watermarking.

Does the tool need an account?

No. Remove LLM Watermark runs free without signing in; an account only raises the daily limit and unlocks the API.

Remove Claude watermarks

Confirmed watermarking for Claude. Paste any Claude output into the scanner above to see exactly what is in it; pick your model below for what to expect from that specific version.

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Paste your text

Cleaned

Invisible charactersZero-width spaces, joiners, bidi controlsVariation selectorsIncluding the U+E0100 supplement and tag charactersLook-alike lettersCyrillic and Greek letters inside Latin wordsExotic spacesNon-breaking, thin and narrow spacesFold punctuationCurly quotes and em dashes to ASCII. Changes styleTidy whitespaceCollapse double spaces and trailing blanks

Claude models

Remove Claude Opus 5 watermarkZero-width characters · Variation selectors · Non-breaking and exotic spacesConfirmed Remove Claude Sonnet 5 watermarkZero-width characters · Variation selectors · Non-breaking and exotic spacesConfirmed Remove Claude Fable 5 watermarkZero-width characters · Variation selectors · Statistical (token-level) watermarksConfirmed Remove Claude Haiku 4.5 watermarkZero-width characters · Non-breaking and exotic spaces · Typographic punctuationLikely Remove Claude Opus 4.8 watermarkZero-width characters · Typographic punctuation · Whitespace patterningLikely Remove Claude Sonnet 4.6 watermarkZero-width characters · Non-breaking and exotic spaces · Typographic punctuationLikely Remove Claude Code output watermarkZero-width characters · Variation selectors · Statistical (token-level) watermarksConfirmed

Background

Where Claude stands

Anthropic announced on 11 August 2026 that every model released after 2 August automatically embeds an imperceptible watermark in generated text and files, to satisfy Article 50 of the EU AI Act, and applied it globally rather than only in the EU. The mark travels with a copy-paste and can survive light editing.

What this cannot do

There are two different things people mean by an AI watermark, and only one of them is something a cleaner can touch.

The first lives in the characters: invisible code points, look-alike letters, unusual spaces. Those are data added to the string, and removing them is exact and verifiable. The report tells you precisely what came out.

The second is statistical. A key biases which words the model picks, so the mark is spread across the word choices themselves and nothing was inserted at all. No character-level tool can remove that, including this one. Only rewriting enough of the wording does, and any site claiming otherwise is selling you something. We would rather say so than let you publish on a false assumption.

Step by step

Paste the textPaste the Claude output into the box at the top of this page. It stays in your browser tab; the scan runs against the characters, not against any account you have.
Read the reportEvery flagged character is listed with its Unicode name and code point, so you can verify the finding in any hex editor rather than taking our word for it.
Copy the clean textThe cleaned copy is byte-identical to what you pasted apart from the characters listed in the report. Nothing is rephrased, and nothing is sent anywhere.

Questions

Does Claude watermark its output?: Confirmed watermarking. Anthropic announced on 11 August 2026 that every model released after 2 August automatically embeds an imperceptible watermark in generated text and files, to satisfy Article 50 of the EU AI Act, and applied it globally rather than only in the EU. The mark travels with a copy-paste and can survive light editing.
Which Claude models are affected?: Claude Opus 5: confirmed watermarking. Claude Sonnet 5: confirmed watermarking. Claude Fable 5: confirmed watermarking. Claude Haiku 4.5: likely watermarked. Claude Opus 4.8: likely watermarked. Claude Sonnet 4.6: likely watermarked. Claude Code output: confirmed watermarking.
Does the tool need an account?: No. Remove LLM Watermark runs free without signing in; an account only raises the daily limit and unlocks the API.