Frequently Asked Questions
What does ROT13 do?
ROT13 shifts each letter 13 positions in the alphabet, so A becomes N, B becomes O, and so on.
Can I use ROT13 to decode as well?
Yes. Because the alphabet has 26 letters, applying ROT13 twice returns the original text, so the same operation encodes and decodes.
Is my text sent to a server?
No. All encoding and decoding happens in-browser.
Example input/output
Input: Hello, World!
Output: Uryyb, Jbeyq!
How it works
This tool shifts each letter 13 positions in the alphabet (A→N, B→O, etc.) using modular arithmetic. Non-letter characters are unchanged. Since the alphabet has 26 letters, applying ROT13 twice returns the original text. Processing runs in your browser.
Common use cases
- Encode text with ROT13 for simple obfuscation in forum spoilers
- Decode ROT13-obfuscated text from online communities
- Test simple Caesar cipher transformations