Unicode Steganography Tools

Advanced tools for hiding secret messages in plain sight using Unicode character features

Zero-Width Characters

Hide secret messages within regular text using invisible Unicode characters. This method embeds data using zero-width characters that are invisible to the human eye but preserved in the text.

  • Binary encoding with 3 zero-width characters
  • Invisible to human readers
  • Works in most text applications
  • Flexible positioning (start, middle, end)
Try Zero-Width Steganography

Emoji Variation Selectors

Hide messages within emojis using Unicode variation selectors. Based on Paul Butler's research, this technique embeds data directly into emoji characters using invisible modifiers.

  • 16 variation selectors (4 bits each)
  • Works with any base emoji
  • High data density
  • Invisible character modifiers
Try Emoji Steganography

Unicode Space Characters

Hide messages using different Unicode space characters with varying widths. Based on research paper techniques that classify spaces into groups for maximum steganographic capacity.

  • Multiple Unicode space characters
  • Group A: Inter-word spaces (4 bits each)
  • Group B: Line-end spaces (2 bits each)
  • Zero-width character combinations
Try Space Steganography

Line Shifting

Hide messages by vertically shifting text lines in formatted documents. Each line is moved slightly up or down to encode binary data, surviving print-and-scan processes.

  • Vertical text line displacement
  • One bit per line of text
  • Survives printing and scanning
  • Imperceptible to human readers
Try Line Shift Steganography

Font Steganography

Hide messages by alternating between two visually similar fonts (LiberationSans and Arial) in PDF documents. Each character's font encodes one bit of secret data.

  • Font-based binary encoding
  • Generates PDF output
  • Visually imperceptible
  • Survives printing and scanning
Try Font Steganography

Letter Shifting

Hide secret messages by subtly shifting letters in cover text images. Each letter's position is offset by one pixel in one of eight directions to encode 3 bits per character.

  • 3 bits encoded per letter via 8 directional shifts
  • Maintains readable text with subtle position changes
  • Supports ASCII uppercase letters and digits
  • Outputs rectangular PNG images
  • Requires letter images generated via setup script
Try Letter Shift Steganography

How Unicode Steganography Works

Unicode steganography leverages special invisible characters within the Unicode standard to embed hidden data. Each method uses different approaches:

Zero-width steganography uses binary encoding with three special characters: U+200C for '0', U+200D for '1', and U+200B as byte separators. Your message is converted to binary and each bit is encoded using these invisible characters.

Emoji steganography uses variation selectors (U+FE00 to U+FE0F) that encode 4 bits each. Your message is converted to UTF-8 bytes, split into nibbles, and each nibble maps to a variation selector appended to the base emoji.

Space steganography uses Unicode space characters of different widths (Thin, Six-Per-Em, Hair, Punctuation spaces) combined with zero-width characters. Spaces are classified into inter-word (Group A) and end-of-line (Group B) categories, each encoding different amounts of data.

Line shifting steganography encodes data by vertically displacing text lines. Each line in a document is shifted up (bit 0) or down (bit 1) by a small amount (1-3 pixels). The shifts are nearly imperceptible but can be detected through centroid analysis of line positions.

All methods preserve data during text transmission while remaining invisible to human readers, making them ideal for covert communication.

Features & Benefits

All tools provide instant encoding and decoding with automatic processing. The interface displays detailed statistics including character counts, encoding overhead, and data capacity to help you understand the steganographic process.

Privacy First: All processing happens locally in your browser through client-side JavaScript. Your messages never leave your device, ensuring complete privacy. The server only provides the interface and API endpoints for processing requests sent from your browser.

Cross-Platform: While these techniques work across platforms supporting Unicode, some applications may normalize or strip special characters. Always test on your target platform. Some code editors and IDEs don't render variation selectors, making them ideal for certain use cases but risky for others.

Security Considerations & Best Practices

Concealment vs Encryption: These techniques provide concealment through obscurity, not cryptographic security. Hidden messages are encoded but not encrypted - anyone who knows the technique can extract them.