📝 Text & List
ROT13 Encoder / Decoder
Encode and decode text with ROT13 cipher. Also supports Caesar cipher with any shift (1–25). Free and instant.
The ROT13 is a free online tool that helps you encode and decode text with rot13 cipher. also supports caesar cipher with any shift (1–25). free and instant It runs in your browser with no sign-up, downloads, or installation needed. All processing happens locally — your data stays on your device.
ROT13
ROT13 substitution table
How to use the ROT13
1
ROT13 — the simplest cipher
ROT13 replaces each letter with the letter 13 positions ahead in the alphabet (A→N, B→O…). Because the alphabet has 26 letters, applying ROT13 twice returns the original text — making it self-reversing. It's used to hide spoilers and answers in online forums.
2
Caesar cipher
Julius Caesar used a shift-3 cipher to protect military messages. The Caesar cipher shifts every letter by a fixed number. With a shift of 3: A→D, B→E, C→F. To decode, shift back by the same amount (or use shift 23 to decode shift 3). ROT13 is simply a Caesar cipher with shift 13.