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 — this page also works as a steganography decoder for invisible Unicode.
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.

Do you have a steganography decoder?

  • Yes. The Decode section functions as a steganography decoder for zero‑width Unicode text. Paste suspicious text and click Decode to reveal any hidden message.

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.