Invisible Character & Zero-Width Space Sanitizer

Client-SideOffline Ready

Detect and strip hidden zero-width spaces, non-breaking spaces, Unicode homoglyphs, and curly smart quotes with live visual highlighting.

Detection Status4 Hidden Characters Detected
Test Presets:

Raw Source Text / Code

275 chars • 9 lines
// This code looks identical to valid JavaScript, but contains U+200B zero-width spaces! const user[ZWSP]Role = "admin"; const auth[ZWSP]Token = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9"; function verify[ZWSP]Access() { if (user[ZWSP]Role === "admin") { console.log("Access granted!"); } }

Detected Invisible Characters Breakdown

U+200B

Zero-Width Space

Category: zero-width
4×

Visual Zero-Width Highlighting

Instantly reveals invisible zero-width spaces (ZWSP, ZWNJ, BOM) and Trojan Source bidi override marks as glowing visual badges.

Smart Quotation & Space Normalization

Converts curly typographical quotes (“ ” ‘ ’) to straight ASCII and replaces non-breaking spaces with standard whitespace.

100% Client-Side Privacy

All Unicode parsing, inspection, and sanitization execute entirely in local memory with zero remote server transmission.

Frequently Asked Questions

What are invisible zero-width characters and why do they cause errors?
Zero-width characters (such as U+200B Zero Width Space, U+FEFF Byte Order Mark, or U+200C/D Joiners) render with zero pixel width on screens but remain in the underlying string, causing mysterious syntax errors, broken JSON parsing, or failed regex matching when code is copied from rich-text apps.
Does this tool convert smart/curly quotes into straight ASCII quotes?
Yes. You can automatically normalize typographical curly single/double quotes (“ ” ‘ ’) into straight ASCII quotation marks (" ') and convert non-breaking spaces (U+00A0) to standard spaces.
Is my text or code sent to any remote server for scanning?
No. All Unicode analysis, visual tag rendering, and sanitization execute 100% locally in your browser memory using JavaScript regular expressions and character code inspection. Your code and confidential text never leave your machine.
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