ROT13 Converter
Apply ROT13 alphabet letter substitution cipher to obfuscate text.
ROT13 Cipher Converter
About ROT13 Converter
The ROT13 Converter is a symmetric letter rotation cipher that shifts every alphabet character by 13 positions (A ↔ N, B ↔ O), providing instant bidirectional text masking for Geocaching hints, game easter eggs, and forum spoilers.
How to Use ROT13 Converter
Step 1
Type or paste text into the input editor.
Step 2
View the ROT13 converted text generated in real time.
Step 3
Toggle ROT5 or ROT47 modes for numbers and symbols.
Step 4
Click "Copy Result".
Practical Use Cases for ROT13 Converter
Forum Spoiler Masking & Geocaching Coordinates
Encode puzzle hints, game cheat codes, and movie spoilers on Reddit and Discord so readers only reveal them intentionally.
Classical Cryptography & ROT5/ROT18/ROT47 Learning
Experiment with Caesar substitution ciphers across alphabet letters, numbers (ROT5), and full ASCII characters (ROT47).
Input & Output Examples
Encoding "Secret Message 123" with ROT13 & ROT5
Text: Secret Message 123
ROT13/5: Frperg Zrffntr 678 (Symmetric: Running again restores original text)
Key Features & Performance
- ✓Symmetric transformation: Encoding and decoding use the exact same algorithm.
- ✓Supports ROT13 (Letters A-Z), ROT5 (Numbers 0-9), ROT18 (Alphanumeric), and ROT47 (Full ASCII).
- ✓Preserves uppercase/lowercase character casing and whitespace.
- ✓100% Client-Side computation.
- ✓1-Click Copy result.
Key Terminology & Definitions
ROT13 Cipher
A simple substitution cipher that replaces a letter with the 13th letter after it in the Latin alphabet.
Involution (Self-Inverse)
A mathematical function that is its own inverse (f(f(x)) = x), meaning applying ROT13 twice returns the original plaintext.