Beaufort Cipher Tool - P00D Geocaching Puzzles

Beaufort Cipher

Enter a message and a keyword. The standard Beaufort cipher is reciprocal, so the same operation is used to encrypt and decrypt.

Keyword

Input

Key stream: —

Output

Output will appear here.

How Beaufort works

Letters are converted to A=0 through Z=25. For each position, Beaufort calculates key letter − message letter modulo 26. The keyword repeats for as long as needed.

Spaces and punctuation are preserved and do not advance the keyword.

Quick Example

With plaintext HELLO and key KEY, the repeating key is KEYKE. Click below to load the example and see the result.