About Zero-Width Character Detector

Find and highlight invisible zero-width characters in text. Part of the DevTools Surf developer suite. Browse more tools in the Fun / Niche collection.

Use Cases

• Debug string comparison failures caused by invisible characters
• Detect watermarked text copied from protected documents
• Clean pasted content before inserting into databases
• Find hidden characters in code that break compilation

Tips

• Paste suspicious text to reveal hidden zero-width characters
• Check for zero-width joiners that affect text rendering
• Scan copy-pasted code for invisible characters causing bugs

Fun Facts

• Zero-width characters (U+200B, U+200C, U+200D, U+FEFF) are invisible but occupy space in strings, breaking comparisons and regex matches.
• Zero-width characters have been used for text watermarking — embedding invisible unique identifiers to track document leaks.
• The zero-width joiner (U+200D) is what makes compound emojis work, joining separate emoji into family, flag, and skin-tone sequences.

FAQ

What zero-width characters does it find?

ZWSP (U+200B), ZWNJ (U+200C), ZWJ (U+200D), BOM (U+FEFF), soft hyphen (U+00AD), and several others. All invisible when displayed normally.

Why are they dangerous?

They pass validation, get copy-pasted, then break regex matching, authentication, and parsing downstream. A username with a zero-width space isn't the same as the visible username.

Where do they come from?

Word processors, some websites, Slack formatting, and intentional steganography. Sometimes malicious (zero-width tracking in docs).

Can I remove them?

Yes — click 'strip' to get a clean version. For programmatic removal, use Clipboard Cleaner which handles a broader range of invisible chars.