Special Character Detector

Zero-width characters are Unicode code points that take up no visible space: zero-width space (U+200B), zero-width non-joiner (U+200C), zero-width joiner (U+200D), and others. They are invisible to the human eye but present in the string. In code, they break string comparisons. In databases, they cause WHERE clause mismatches. In passwords, they make credentials appear identical but fail authentication.

The most common source is copy-pasting from websites, PDFs, Word documents, or messaging apps. Rich text editors insert invisible formatting characters. Some websites deliberately embed tracking characters. AI-generated text sometimes includes soft hyphens or non-breaking spaces.

The BOM is the character U+FEFF placed at the start of a file to indicate its encoding. Some Windows programs prepend this to UTF-8 files. When pasted into code or databases, it appears as a corrupt first character and is nearly impossible to spot visually.

Yes. A variable name with a zero-width space looks identical to one without but is treated as a different identifier. SQL queries with invisible characters in string literals fail to match database values. JSON keys with hidden characters cause parse errors or silent data loss.

Once you identify which characters are present using this tool, use a text editor with regex support (VS Code, Notepad++) to find and remove them. The regex [\u200B-\u200D\uFEFF] targets common zero-width characters.

U+200F is an invisible character that changes text direction to right-to-left. When embedded in filenames or URLs, it can be used to disguise malicious file extensions (e.g. making a .exe look like .jpg). Always check downloaded filenames for RTL/LTR marks.

Completely free. Paste any amount of text and get an instant character-by-character analysis with no limits.