Zero-Width Steganography

This tool uses invisible Unicode characters to hide messages within ordinary text:

• 0 → U+200C (Zero-Width Non-Joiner)
• 1 → U+200B (Zero-Width Space)
• sep → U+FEFF (Zero-Width No-Break Space)

Each character in the secret message is converted to its binary representation, then each bit is replaced with an invisible zero-width character. In text mode, the payload is inserted between the first two visible characters. In emoji mode, the payload is embedded directly inside a single emoji — the emoji looks identical but carries the hidden data.

Zero-width steganography is particularly dangerous because the modified text is visually identical to normal text. There is zero visible difference between a clean message and one carrying a hidden payload.

• • Standard copy/paste preserves the invisible characters — the payload travels silently across platforms
• • Most content filters and moderation tools only scan visible text and completely miss zero-width payloads
• • A single emoji like 😈 can carry an entire hidden message while looking completely normal
• • Character count in most editors won't reveal the extra invisible characters — only hex inspection exposes them

This makes it a potential vector for data exfiltration, covert communication, watermarking text to track leaks, or bypassing content filters that rely solely on visible text analysis.