Hidden characters · Free · In your browser
Reveal the zero-width, watermark, and bidirectional characters hiding inside pasted or AI-generated text - then strip them in one click.
Invisible characters are code points with no visible glyph (zero-width spaces, joiners, bidi controls) that can watermark text, break search, or corrupt code.
Paste any text to reveal hidden Unicode - or try an example:
🔒 Nothing leaves your browser.
0 chars scanned
Hygiene score
Paste text to scan
🔒 Runs entirely in your browser - open DevTools → Network and you'll see zero requests. Works offline.
The short version
There is no server and no upload. Everything runs with plain JavaScript on your device, so you can safely work with confidential or unpublished text. Open your browser's DevTools Network tab while you use it and you'll see zero requests - and it keeps working with your connection turned off.
In the margin
A code point that takes up no visual space, such as the zero-width space (U+200B) or zero-width joiner (U+200D). They’re invisible on screen but still present in the text, which is how they end up watermarking or corrupting a paste.
Some AI tools and documents insert invisible characters to track or fingerprint text. They’re harmless to read but can flag a paste as machine-generated or break code and spreadsheets.
No. Everything runs in your browser with plain JavaScript - your text is never uploaded, stored, or logged. Open your browser’s DevTools Network tab while you use it and you’ll see zero requests. The tool also works offline.
Margin note
Every tool here runs 100% in your browser. Open DevTools → Network while you use one and you'll see zero requests - your text never leaves your device. Prefer the deep dives? Read the writing on Penluma.