Classic Ciphers
Encode and decode ROT13, Caesar, Atbash, and Vigenère ciphers. Case, digits, and punctuation are preserved — everything runs in your browser.
Educational ciphers — trivially breakable, never use for real secrecy.
0 / 100,000 characters
ROT13 is its own inverse — the same transform encodes and decodes, so both panes below show one pass over your text.