Encode and decode text using ROT13 cipher substitution for simple text obfuscation. ROT13 Encoder/Decoder is a free online tool from the ToolsRift Text Encoding Tools collection. It runs entirely in your browser — nothing to install, no signup, and your data never leaves your device.
ROT13 is a simple letter substitution cipher that replaces each letter with the letter 13 positions after it in the alphabet. A becomes N, B becomes O, etc.
ROT13 is used to obscure text (like spoilers or puzzle answers) without true encryption. It's easily reversible—applying ROT13 twice returns the original text.
No, standard ROT13 only affects letters A-Z. Numbers and special characters remain unchanged.