Caesar Cipher & ROT13
Encode or decode text using classical Caesar cipher, ROT13, or brute-force all 25 possible shifts
Shift Amount3
Direction
Quick Shift:
Encoded · shift 3
Alphabet Mapping
PlainABCDEFGHIJKLMNOPQRSTUVWXYZ
CipherDEFGHIJKLMNOPQRSTUVWXYZABC
A Brief History of Classical Ciphers
From Julius Caesar's military dispatches to internet spoiler culture — classical ciphers shaped how we think about secrecy.
~100 BCJulius Caesar
Shift cipher with key 3, used in military communications
1563Vigenère Cipher
Polyalphabetic substitution, harder to crack
1987ROT13
Internet standard for hiding spoilers and jokes
1977AES Predecessor
DES introduced — the start of modern symmetric encryption