Detects 10+ invisible characters
Find zero-width spaces, BOM characters, Unicode spaces, bidirectional marks, and selected non-printing controls.
Unicode text utility
Hidden Character Detector
Find and remove invisible characters, zero-width spaces and AI watermarks — the AI-powered hidden character checker trusted by writers and developers.
Detect locally in your browser. Your pasted text is not uploaded or saved by this first version.
Local Unicode scan
Scan your text for hidden characters
Paste text below to see invisible characters highlighted in their original positions.
Your text stays in this browser. The daily count is stored locally and does not include the text you paste.
Your highlighted result will appear here
Run Detect to inspect code points, Unicode names, and occurrence counts before cleaning.
Clearer text, fewer surprises
A practical hidden character detector for copied text
Hidden Unicode marks are easy to miss because the visible sentence can look completely normal. This checker makes those marks inspectable before they cause search, validation, formatting, or publishing problems.
Zero-width & Unicode-aware
The scanner walks Unicode code points correctly, so emoji, surrogate pairs, line breaks, and repeated marks are counted predictably.
AI watermark remover
Clean invisible Unicode patterns that may appear in AI text workflows. Detection alone cannot prove where text came from.
Free, no sign-up
Check up to 2,000 Unicode characters per run and use the browser-based tool for 20 free checks per UTC day.
What the scanner checks
It recognizes zero-width space U+200B, zero-width non-joiner U+200C, zero-width joiner U+200D, the BOM character U+FEFF, non-breaking space U+00A0, Unicode spaces from U+2000 through U+200A, directional marks, selected bidirectional controls, soft hyphen, word joiner, invisible operators, line separators, and selected non-printing controls.
What it leaves alone
Normal letters, punctuation, emoji, regular spaces, tabs, and ordinary line breaks are not treated as hidden characters. Counts use Unicode code points instead of UTF-16 storage units, so an emoji does not produce a misleading extra character in the summary.
A hidden character is not automatically malicious or proof of an AI watermark. The result is a transparent Unicode inspection, not a claim about authorship.
Three simple steps
How to find and remove invisible characters
The tool keeps inspection and cleanup separate. You can review every highlighted position first, then create a clean copy without overwriting your original input.
Paste
Paste copied text into the scanner. The original stays in the input until you choose an action.
Detect
See every flagged character in place, with its Unicode name, code point, and total count.
Clean
Remove zero-width controls, normalize Unicode spaces, and copy a readable clean-text result.
Questions answered
Hidden character detector FAQ
Learn what the checker can identify, how cleaning behaves, and what the first browser-based version does with your text.
What is a hidden character?
A hidden character is a Unicode code point that affects text without displaying as a normal visible symbol. Common examples include zero-width spaces, non-breaking spaces, and bidirectional controls.
Why does AI-generated text contain invisible characters?
Invisible characters can enter AI-generated text through formatting, copy and paste, document editors, or watermarking experiments. Their presence alone does not prove that text was generated by AI.
Can this invisible character checker find zero-width spaces?
Yes. It detects U+200B, U+200C, U+200D, U+FEFF, and other selected Unicode spacing, formatting, and control characters, then shows their names, code points, and counts.
Will detection change my original text?
No. Detect only creates a highlighted view. Your original input stays unchanged until you choose Remove All and create a clean result.
How many characters can I check for free?
The free tool accepts up to 2,000 Unicode characters per check and allows 20 checks per UTC day in the browser. Pro access is reserved for a future release.
Does the AI hidden character detector store my text?
No text is uploaded or stored by this first version. Detection runs in your browser, and only a local usage counter is saved to enforce the free limit.
What happens when I remove hidden characters?
Zero-width and formatting controls are removed. Non-breaking and Unicode spacing characters are normalized to regular spaces, and line separators are normalized to line breaks so readable spacing is preserved.
Which Unicode characters does it detect?
The detector covers zero-width characters, U+00A0, U+2000-U+200F, selected bidirectional controls, soft hyphen, word joiner, BOM, line separators, and selected non-printing controls. The result list shows each exact code point.
Go deeper
Guides to invisible text and Unicode
Use these practical articles to understand hidden code points, AI text watermark claims, and safe cleanup workflows.
What Is a Hidden Character?
Understand zero-width characters, Unicode spaces, control marks, and their code points.
Read the guideWhy AI-Generated Text Contains Invisible Characters
Separate ordinary formatting artifacts from claims about AI text watermarks.
Read the guideHow to Remove Invisible Characters from Text
Follow a practical workflow for inspecting, cleaning, and verifying copied text.
Read the guide