Caesar Shift (Substitution Cipher)

A Caesar Shift cipher is a type of mono-alphabetic substitution cipher where each letter of the plain text is shifted a fixed number of places down the alphabet. For example, with a shift of 1, letter A would be replaced by letter B, letter B would be replaced by letter C, and so on. This type of substitution Cipher is named after Julius Caesar, who used it to communicate with his generals.

This type of cipher is a form of symmetric encryption as the same key can be used to both encrypt and decrypt a message. (e.g. If a message is encrypted with a key of +5, it can be decrypted with a key of -5).

A cipher wheel is a tool used to help decipher a message encrypted using the Caesar cipher:

You can generate your own encryption keys and encrypt your own messages using our online Caesar Shift substitution engine:

Frequency Analysis

One approach used to help decrypt a Caesar shift substitution cipher is to use a frequency analysis based on counting the number of occurrence of each letter to help identify the most recurrent letters. (e.g. In the English language, letters E, T and A).

Your Task:

Complete a frequency analysis to decrypt the following ciphers.