ROT13 & Cipher Tools
Encode or decode text using ROT13 and other rotation ciphers.
About ROT13 & Cipher Tools
ROT13 (rotate by 13 places) is a simple letter substitution cipher that replaces a letter with the 13th letter after it in the alphabet. It's a special case of the Caesar cipher, developed in ancient Rome.
ROT13 Cipher
ROT13 shifts each letter 13 positions in the alphabet. Since the English alphabet has 26 letters, applying ROT13 twice returns the original text.
How Rotation Ciphers Work
Rotation ciphers substitute each letter in the plaintext with a letter some fixed number of positions down the alphabet. ROT13 is a special case where the shift is exactly half the alphabet, making it self-reciprocal (applying it twice returns the original text).
For example, in ROT13:
- A becomes N
- B becomes O
- Z becomes M
The tool supports several variants: ROT13 (for letters), ROT5 (for digits), ROT18 (ROT13+ROT5), ROT47 (for most printable ASCII characters), and custom rotation values.
Key features of this tool:
- Multiple cipher types: ROT13 (letters), ROT5 (digits), ROT18 (both), ROT47 (ASCII chars)
- Custom rotation: Choose any shift value from 1-25 for alphabetic characters
- Flexibility: Options to preserve case and non-cipher characters
- Bi-directional: Easily swap output back to input for repeated transformations
The tool works in real-time, converting your input text as you type based on the selected cipher and options.