Caesar Cipher

A simple substitution cipher where each letter is shifted by a fixed number of positions in the alphabet

Caesar Cipher Tool

Shift Value

Input Text

Output

The Caesar cipher shifts each letter in the plaintext by a fixed number of positions in the alphabet.

Example with shift 3:

A → D, B → E, C → F, ..., X → A, Y → B, Z → C

"HELLO" → "KHOOR"

To decrypt, shift in the opposite direction (subtract the shift value).

Original:A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Shifted:D E F G H I J K L M N O P Q R S T U V W X Y Z A B C

Named after Julius Caesar, who used it with a shift of 3 to protect military communications.

One of the simplest and most widely known encryption techniques.

Security: Easily broken by frequency analysis or brute force (only 25 possible keys).