ROT13 Encoder
Apply the ROT13 cipher to text.
Online ROT13 Cipher & Caesar Cipher +13 Tool
Easily encode or decode text using the classic ROT13 substitution cipher, perfect for spoilers, puzzles, and basic obfuscation.
How to use the ROT13 Tool:
- Type or paste your text into the input box.
- The encoded output appears instantly in the box below.
- Copy the result to share hidden messages that can be easily revealed by running them back through the tool.
How does ROT13 work?
ROT13 ('rotate by 13 places') is a simple Caesar cipher that replaces each letter with the one 13 places ahead of it in the alphabet. Because the English alphabet has 26 letters, the cipher is its own inverse—applying it a second time restores the original message. It’s a fun, non-secure way to hide text in plain sight.