Encode and decode substitution ciphers, ASCII ROT47, and brute-force 25 Caesar shifts.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. Zero egress.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
Choose ROT13, ROT5, ROT18, ROT47, or Caesar Shift mode.
Paste your obfuscated text string into the input area.
Copy the transformed plain text or explore the 25-shift comparison matrix.
Yes, applying ROT13 twice to any text restores the original message because the English alphabet has 26 letters (13 + 13 = 26).
ROT13 rotates only the 26 Latin letters, while ROT47 rotates all 94 printable ASCII characters (letters, numbers, and punctuation).
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