Invisible Unicode Character Detector
Find zero-width spaces, BOMs, bidi controls and 50+ other invisible characters — highlighted, located, and removable in one click.
Tool input is processed locally in your browser and is not submitted to CodeNimbleTools. Avoid pasting production secrets into any device or website you do not fully trust.
Hidden characters (zero-width spaces, BOMs, bidi controls…) will be highlighted here.
About this tool
Invisible Unicode characters break code, corrupt data, defeat string comparisons and enable filename spoofing — and you can't see any of it. This detector scans for 50+ invisible and deceptive characters: zero-width spaces and joiners, byte-order marks, non-breaking spaces, soft hyphens, bidi override controls, variation selectors and exotic space characters.
Every finding is highlighted inline with its code point, named in a summary table with positions, and Copy cleaned text strips them all (converting invisible spaces to normal spaces) in one click.
How to use it
- Paste suspicious text — from a website, PDF, chat, or a config that "looks right but fails".
- Findings appear instantly: a table of characters and a highlighted view.
- Hover any highlight to see the character's name and code point.
- Click Copy cleaned text to get a sanitized version.
Useful ways to apply it
- Debugging "identical" strings that won't compare equal.
- Cleaning text copied from PDFs or rich-text editors before it enters code.
- Detecting right-to-left override tricks in filenames (invoice_exe.txt style spoofing).
- Sanitizing user-submitted content that hides zero-width watermarks.
Worked example
Example input
user[U+200B]nameExpected output
Flags U+200B ZERO WIDTH SPACE between “user” and “name”Edge cases to check
- Some invisible characters are legitimate in languages or protocols.
- Normalization does not remove every security-relevant confusable character.
- Copy/paste may change line endings or normalization before inspection.
Known limitations
Detection is an inspection aid, not a complete Unicode security analyzer or malware scanner.
How this tool was reviewed
Reviewed with zero-width space, non-breaking space, BOM, directional marks and ordinary controls.
Standards and technical references
See the site-wide testing methodology for fixture categories, privacy checks and correction policy.
Frequently asked questions
Which characters are detected?
What does cleaning do exactly?
Why do these characters exist at all?
Privacy
Tool input is processed locally in your browser and is not submitted to CodeNimbleTools. Avoid pasting production secrets into any device or website you do not fully trust.