A free Claude watermark remover and checker that runs entirely in your browser — it strips invisible characters, repairs look-alike letters that break your SEO, and scores how much watermark your text could actually carry.
Scan and clean your text
Nothing is uploaded. All processing happens on this page, in your browser.
The only tool that bypassed Pangram and Turnitin in 2026.
Most humanizers clear one detector and get caught by the other. StealthWriter is the one that gets past both — run Ghost 5.2 Pro at level 7–8, section by section, and re-check before you submit.
Try StealthWriter →What this tool cannot do — and neither can any other
Claude’s actual text watermark is not a character hidden in your text. It is a bias in which word the model chose, seeded by a private key. There is nothing in the text to find and nothing to strip.
Detecting it requires Anthropic’s key. Anthropic announced a detection API on 14 August 2026 and has not shipped it. So no public tool can tell you whether a given passage carries the mark — including this one. Any site claiming otherwise is guessing.
What genuinely removes a statistical watermark is rewriting: published evaluation of this method recorded 98.3% removal after a single paraphrase pass. What does not remove it is deleting zero-width characters, which is what most “Claude watermark removers” actually do. Full breakdown of the mechanism and the evidence.
What this Claude watermark remover actually removes
It removes
- Invisible characters — zero-width spaces, joiners, word joiners, byte-order marks, soft hyphens, directional marks (24 code points)
- Odd spaces — non-breaking, narrow, hair, en/em and ideographic spaces normalised to a plain space (15 code points)
- Look-alike letters — Cyrillic and Greek characters masquerading as Latin, converted back (50+ mappings)
- Typography tells — em dashes, smart quotes and ellipses, optionally
It cannot remove
- The statistical watermark — it lives in word choice, not characters
- C2PA metadata in files — that is on images and PDFs, not pasted text
- Anything in text you have not pasted here — nothing is fetched or uploaded
The look-alike letter problem most removers create
This is the part that separates a checker from a liability. A common “watermark removal” tactic is to swap Latin letters for identical-looking Cyrillic or Greek ones — a Latin a becomes a Cyrillic а. To your eye, nothing changed. To a search engine, the word is now a different string entirely.
Search engines resolve entities, not letters. A homoglyph inside a brand name, a city, or a service term does not degrade gracefully the way a typo does — the entity resolves to nothing at all. Mixed-script text is also widely understood to be a spam signal. If you have run text through a removal tool before, scan it above: this checker flags every affected word and converts it back.
How to use the checker
Paste your text and press Scan text for a read-only report — character counts, affected words, and a carrying-capacity score. Press Clean text to apply the options you have ticked; the textarea is rewritten in place so you can copy it straight out. Smart quotes and dashes are off by default, because they are legitimate typography rather than a watermark, and stripping them makes writing look worse for no benefit.
The carrying capacity score is not a detection result. It measures how much room your text gives a word-choice watermark: prose with many interchangeable words scores high, while text dense with figures, dates and proper nouns scores low, because there was never much for a watermark to attach to.
Frequently asked questions
Does this Claude watermark remover actually remove Claude’s watermark?
It removes invisible characters, odd spaces and look-alike letters, which is what most tools marketed as watermark removers do. It does not remove Claude’s statistical watermark, because that lives in word choice rather than in any character. No browser tool can remove it; only rewriting the text does that.
Can any tool check whether text carries Claude’s watermark?
Not publicly. Detection requires Anthropic’s private key, and the detection API announced on 14 August 2026 has not shipped. Tools claiming to check your text for the mark are inspecting Unicode artifacts instead, which is a different thing entirely.
Is my text uploaded anywhere?
No. The scanner and cleaner run in JavaScript on this page. Nothing is transmitted, logged or stored on a server, and the page keeps no copy after you close it.
Will removing these characters help my SEO?
Removing look-alike letters can genuinely help, because they break entity resolution. Removing zero-width characters is harmless housekeeping with no documented ranking effect. Google’s spam policy contains no reference to watermarks and targets scaled content abuse “no matter how it’s created.”
Why are smart quotes and em dashes off by default?
Because they are ordinary typography, not watermarks. Some tools strip them to make text look less AI-written, but that is a style choice with a real cost to readability — so it is opt-in here.
Does editing my text remove the watermark?
It degrades it. Published evaluation of this watermark family recorded 98.3% removal after one meaning-preserving paraphrase pass, and an 80% baseline false-negative rate before any attack at all. Both figures were measured on SynthID generally, not on Claude’s deployed build, which cannot be tested from outside.
Sources
- Anthropic. “How Claude’s text watermarking works.” anthropic.com. Accessed 27 Aug 2026.
- Anthropic Help Center. “How Claude marks AI-generated content.” support.claude.com. Accessed 27 Aug 2026.
- Tamim & Khan. “AI Watermark Evidence Fails Forensic Readiness.” arxiv.org. Accessed 27 Aug 2026.
- Google Search Central. “Spam policies for Google web search.” developers.google.com. Accessed 27 Aug 2026.
- Unicode Consortium. “UTS #39: Unicode Security Mechanisms.” unicode.org. Accessed 27 Aug 2026.
The only tool that bypassed Pangram and Turnitin in 2026.
Most humanizers clear one detector and get caught by the other. StealthWriter is the one that gets past both — run Ghost 5.2 Pro at level 7–8, section by section, and re-check before you submit.
Try StealthWriter →