Caesar cipher

The Caesar cipher is a simple substitution cipher that shifts each letter a fixed number of places along the alphabet.

Last reviewed: 2026-10-03

In more detail

With a shift of 3, HELLO becomes KHOOR. ROT13 is the special case with a shift of 13, so applying it twice returns the original (HELLO to URYYB and back). With only 25 possible shifts it is broken by trying them all, so it offers no real security.

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Caesar Cipher

Encrypt and decrypt text with the Caesar cipher using any shift from 0 to 25.

ROT13 / Caesar Cipher

Encode or decode text with ROT13 or a custom Caesar cipher shift, computed instantly in your browser.

Fancy Text Generator

Convert text into bold, italic, script, fraktur, double-struck, monospace, circled, small caps.

In more detail

Try these tools

Caesar Cipher

ROT13 / Caesar Cipher

Fancy Text Generator

See also