StegZero

Hide secret messages in plain sight using zero-width characters

Secure
Invisible
Instant
Input
Process
Result

Encode Message

This text will be visible to everyone - choose something natural and inconspicuous
Keep it short and simple for better concealment
Encode your hidden message into the visible text using zero-width characters
Encoded message will appear here.
Copy the encoded message to your clipboard

Decode Message

Paste any text that might contain hidden zero-width characters
Decode any hidden messages from the provided text
Decoded message will appear here.
Copy the decoded hidden message to your clipboard

How StegZero Hides Messages Using Zero-Width Characters

What is Steganography?

  • Steganography is the practice of concealing messages or information within other non-secret text or data.
  • It can be used to hide text within images, audio files, video files, or even other text files.
  • The goal is to ensure that the presence of the hidden message is not detectable by casual observation.
  • Steganography is often used in conjunction with cryptography to provide an additional layer of security.

Use Cases

  • Hide text in text in plain sight using zero‑width Unicode characters (ZWSP/ZWNJ/ZWJ)
  • Reveal invisible text encoded with StegZero using a zero‑width decoder

The Technical Process of Hiding Messages

  • Converts your hidden message to UTF-8 bytes for full Unicode support.
  • Adds a compact header with a magic marker, version, random nonce, length, and CRC32 for integrity.
  • Obfuscates only the payload bits using a nonce-seeded PRNG (not encryption) to reduce easy pattern detection.
  • Maps 3-bit groups to a diversified set of eight zero-width/invisible characters (not just a single 0/1 pair).
  • Evenly interleaves the hidden characters across the visible text so they are not clustered at the end.
  • On decoding, extracts the zero-width alphabet, validates the header and CRC, then restores the UTF-8 message.
  • Includes a legacy fallback decoder for older texts that used a simple two-character (0/1) scheme.

Limitations of Zero-Width Steganography

  • Not all platforms or text editors preserve zero-width characters, which can result in the loss of the hidden message.
  • Zero-width steganography is not suitable for secure communication, as it can be detected by those familiar with the method.
  • Some text editors or platforms may strip invisible characters, rendering the hidden message unreadable.
  • This method should only be used where security is not a primary concern.

Frequently Asked Questions

What is zero‑width steganography?

  • It hides messages using invisible Unicode characters like zero width space (ZWSP), zero width non‑joiner (ZWNJ), and zero width joiner (ZWJ).

Is zero‑width steganography secure?

  • No. It’s an obfuscation technique, not encryption. Avoid using it for sensitive data.

Which characters does StegZero use?

  • A diversified set of zero‑width/invisible Unicode characters to encode bits across your visible text.

How do I encode or decode?

  • Use the Encode and Decode sections above to generate or reveal invisible text.

Important Note

This tool is intended for educational and entertainment purposes only. It is not a secure encryption method and should not be used for sensitive or confidential information. For secure communication, consider using proper encryption tools.