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Free AI Watermark Detection & Removal Tool

Detect and remove hidden Unicode watermarks in AI-generated text. Free for up to 500 words — sign in for longer documents and full results.

Your Text

0 / 500 words · 20 of 20 checks left this hour ·

Your text is processed on our server to generate results. We do not store the content of your text.

Need to pass AI detection?

This tool strips hidden Unicode characters. To address deeper AI writing patterns, use our humanizer or run a full AI scan on the home page.

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What are AI Watermarks?

Unicode Watermarks

AI systems may embed invisible Unicode characters in generated text to identify AI-produced content.

Character Detection

Our tool detects and categorizes invisible watermark characters by type.

More free watermark tools

Specialized checkers for different AI models, platforms, and use cases — all using the same detection engine.

Why check AI text for invisible watermarks?

When you copy text from ChatGPT, Claude, Gemini or other AI tools, invisible Unicode characters can ride along with the visible words. They do not show on screen, but they can break formatting in Word or Google Docs, trip integrity scanners, or fingerprint your text back to the model that produced it.

Our free checker scans pasted text for zero-width spaces, soft hyphens, byte-order marks and other non-printing characters — then returns a cleaned copy you can submit or publish with confidence.

Who uses a watermark checker?

Students paste AI drafts into essays and LMS uploads. Freelancers deliver client copy through CMS fields. SEO teams publish AI-assisted articles to WordPress. In each case, a quick Unicode scan takes under a minute and prevents hard-to-debug formatting issues later.

How to check AI text for invisible watermarks

Checking a piece of AI-generated text for invisible watermarks takes less than a minute:

  1. Copy your AI-generated text. Copy the text you want to check from ChatGPT, Claude, Gemini, or wherever it was produced.
  2. Paste into the checker. Paste the text into the input box on this page.
  3. Run the check. Click Check for watermarks. The tool scans for invisible Unicode characters and hidden formatting markers in seconds.
  4. Copy the cleaned output. Review the detection report, then copy the cleaned, watermark-free version of your text.

What kinds of watermarks we detect

AI systems can hide two broadly different kinds of signal in their output. Our checker is specifically built to detect and remove the first kind — invisible Unicode characters. The second kind, statistical watermarks, requires rewriting to neutralise.

Invisible Unicode watermarks

These are real characters inserted between visible letters that don't render on screen. They travel with copy-paste, get carried into Word documents, Google Docs and CMS fields, and can fingerprint text back to the model that produced it. The checker scans for:

  • Zero-width space (U+200B)
  • Zero-width non-joiner (U+200C) and zero-width joiner (U+200D)
  • Word joiner (U+2060)
  • Soft hyphen (U+00AD)
  • Variation selectors (U+FE00 - U+FE0F)
  • Left-to-right and right-to-left marks (U+200E / U+200F)
  • Byte order mark / ZWNBSP (U+FEFF)
  • Other non-printing formatting characters commonly used as covert channels

Statistical (cryptographic) watermarks

These are patterns in which words the model chooses. They are imperceptible in any one sentence and only emerge over many words. A Unicode scan cannot remove them — to neutralise a statistical watermark you typically need to lightly rewrite the text. Our guide to natural AI writing techniques covers how to do this without losing meaning.

Frequently asked questions

What is an AI watermark checker?

An AI watermark checker is a tool that scans text for hidden watermark signals left by AI models like ChatGPT. It flags invisible Unicode characters (such as zero-width spaces and soft hyphens) and other non-printing markers that indicate the text was machine-generated, then returns a cleaned copy with those characters removed.

How do I check AI text for watermarks?

Copy the text from ChatGPT, Claude, Gemini or any other AI tool, paste it into the checker above, and click Check. The tool scans for invisible Unicode watermark characters and returns a detection report plus a cleaned version of the text you can copy.

Are AI watermarks visible to the human eye?

No. AI watermarks are invisible by design. Unicode-based watermarks use zero-width and non-printing characters that do not render on screen, so you need an automated checker to reliably detect them.

Does the watermark checker also remove watermarks?

Yes. The checker detects invisible Unicode watermark characters and strips them out, returning a clean copy of your text with the original meaning and formatting intact.

Is the watermark checker free?

Yes. The Human Writes watermark checker is free for up to 500 words without an account. Sign in for longer documents, full cleaned text, and character-level breakdowns.

Is my text stored when I use the checker?

We process your text only to return a detection report and cleaned output. We do not retain the content of your pasted text for any other purpose.

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