Detects 10+ invisible characters
Find zero-width spaces, BOM characters, Unicode spaces, bidirectional marks, and selected non-printing controls.
Private Unicode inspection
Hidden Character Detector. See what your text is hiding.
Find zero-width spaces, Unicode formatting marks, and other invisible characters before they break search, validation, formatting, or publishing workflows.
Runs in your browser No text storage Unicode-aware results
Zero-width spacesUnicode whitespaceBidirectional marksBOM and controls
Local Unicode scan
Scan your text for hidden characters
Paste text below to see invisible characters highlighted in their original positions.
Upload a file or imageDrop it here or choose one from your device.TXT, MD, CSV, JSON, DOCX, PDF, PNG, JPG, WEBP · 12 MB max
Detection stays in your browser. When you click Detect, the text (including imported file text) is sent to the server only to authorize your quota and is not stored.
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
Guests can check up to 1,000 Unicode characters per run, three times per day without signing up.
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?
Guests can run up to 3 checks per day with 1,000 Unicode characters per check. Signed-in free accounts can run up to 10 checks per day with 3,000 characters per check. Active Pro subscriptions allow up to 100,000 characters per check without the free daily cap.
Does the AI hidden character detector store my text?
Detection runs in your browser. The application server receives the text only to authorize the individual quota request and does not store the submitted content; it keeps a date-based usage count to enforce daily limits.
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 guideNeed a deeper inspection?
Check Unicode names, code points, and text encoding
Inspect every distinct character, including marks beyond the detector's common hidden-character rules.