Invisible Character Detector

Invisible Character Detector - Find Hidden Characters in Text

Detect invisible and non-printable characters that can cause hard-to-find bugs. Identifies zero-width spaces, BOMs, and more.

Paste text into the input field and the detector highlights all invisible, non-printable, and zero-width characters. Detected characters include zero-width spaces (U+200B), zero-width non-joiners, zero-width joiners, byte order marks (BOM), soft hyphens, and other Unicode control characters. Each occurrence is marked in the text with a colored indicator and labeled with its Unicode code point and name. A summary shows the total count of each invisible character type. Detection runs entirely in your browser.

Developers debug copy-paste errors where code looks correct but won't compile due to hidden Unicode characters. Web designers investigate layout issues caused by zero-width spaces breaking word wrapping. Data analysts clean datasets where invisible characters contaminate string fields, breaking joins or comparisons. Security teams detect obfuscated phishing URLs where zero-width characters hide the real domain.

Zero-width spaces (ZWSP) are the most common culprit—they appear when copying from PDFs or web pages with specific rendering. Byte Order Marks (BOM) at file starts can break parsers expecting plain UTF-8. Soft hyphens (U+00AD) are legitimate in typesetting but cause problems in code or data fields. Right-to-left marks (RLM/LRM) affect text direction rendering; they're invisible but semantically important. Use regex /[​-‏]/g to programmatically strip common invisible characters after detection.

All processing happens directly in your browser. Your files never leave your device — no server uploads, no cloud storage, no data retention. The tool works offline once loaded, requires no registration, and is completely free with no usage limits.