ROT13 Encoder/Decoder

Encode or decode text using the ROT13 substitution cipher.

Simple cipher

ROT13 is symmetric - Encode & Decode are the same!

Enter plain text → get encoded output. Enter encoded text → get decoded output. The same operation works both ways!

Input (Plain or Encoded Text)
Result (Encoded ↔ Decoded)

💡 How to Use

To Encode:

Type "HELLO" → Get "URYYB"

To Decode:

Type "URYYB" → Get "HELLO"

The magic: ROT13 rotates each letter 13 positions. Since there are 26 letters, applying it twice returns the original. Click Swap to move the result back to input and verify!

Alphabet Mapping

Original

ABCDEFGHIJKLMNOPQRSTUVWXYZ

ROT13

NOPQRSTUVWXYZABCDEFGHIJKLM