Invisible Character Checker
Paste text to detect and fix hidden character contamination instantly.
Text is never uploaded. Analysis runs entirely in your browser.
100% browser-side processing / no upload
How to use
- Paste text and analysis starts automatically.
- Check the summary and list to see type, count, and position.
- Switch display mode to inspect issues more clearly.
- Use Clean Copy to copy corrected text.
Examples
Paste corruption check
Input: Text with mixed NBSP and ZWSP
Output: Detects NBSP and ZWSP, then fixes with the general preset
Code and JSON inspection
Input: JSON string with BOM or control character contamination
Output: Removes risky characters with the code/JSON preset
FAQ
Is my text sent to a server?
No. Processing is performed locally in your browser.
Can it detect newline-related issues?
Yes. It detects CRLF/LF/CR and U+2028/U+2029 and lists them with positions.
I am worried about unintended changes.
Use the Minimal Changes preset to target only risky characters.
Can I share a report with teammates?
Yes. Use Copy Report to export type/count/position details as plain text.
Glossary
- ZWSP
- A zero-width space (U+200B) that is invisible on screen.
- NBSP
- A no-break space (U+00A0). It can break matching when mixed with regular spaces.
- Bidi control characters
- Characters that alter display direction and can cause rendering confusion or security issues.
Notes
- Always review transformed text before using it in production workflows.
- Clipboard content can be read by other apps. Use caution on shared devices.
- Input is not persisted. Reloading the page clears the current text.