What is the Caesar Cipher Decoder?

In this post we will be helping you to get familiar with the Caesar Cipher, a simple method of encryption. In doing so, you will be able to apply the cipher to encrypt a plaintext message, and decrypt a ciphertext message.

I addition, we will look at the reasons why the Caesar Cipher is so easily cracked!

So Lets have a look at the Caesar Cipher. You can watch this video below, or further down I walk you through the video steps.

The Caesar Cipher Decoder

In this illustration we can see the Caesar Cipher Decoder. So you have the larger plaintext ring with the 26 letters of the alphabet, and you have the inner ring which is for cipher text. You will see that the key = 19. This means that the inner ring for the cipher text has been moved 19 places. For example, a Key of 0 means that the two red A’s are lined up together so that Z = z, and T = t etc.

Now if the Key is 1, then A = b, C = d etc. so you can make an encrypted message from this simple cypher. Problem is, its easy to crack!

How To Create The Caesar Cipher Decoder

Check out the steps to create a Caesar Cipher Decoder message below:

Write down the alphabet — Caesar Cipher decoder – Write down the Alphabet – A-Z on a sheet of paper. So this will represent your standard Alphabet.

Choose a number that represents the "Key" — Steps 2 : You choose a number between 1 to 26. this number will represent the “Key ” value that will be used to “shift” the alphabet.

Move your alphabet the required spaces

Step 3 : Count the amount of spaces to the right using the number that you chose in the previous step. In the example above where the key is 3, the alphabet is moved 3 spaces. So write another alphabet underneath the original one, starting under the third letter.

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Step 4 – At the end of the alphabet, take the missing letters and add them at the front. So in the example above, XYZ are added at the front of the new alphabet. The bottom row will now be known as the cipher alphabet.

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Why is the Caesar Cipher easy to crack?

There are only 25 possible keys, Caesar ciphers are very vulnerable to a “brute force” attack, where the decoder simply tries each possible combination of letters.
Various methods have been detected which crack the cipher text using frequency analysis and pattern words. One of the approaches is using brute force to match the frequency distribution of letters.

There are two primary methods of breaking the code:

One method is to create a list of words that could be the possible key phrase and attempt a brute force attack.
Another method is to employ frequency analysis. This is the standard method for breaking any substitution cipher.

Caesar Cypher Decoder Tools :

https://www.dcode.fr/caesar-cipher – this is a tool that can be used

https://cryptii.com/pipes/caesar-cipher – Another Tool

https://www.boxentriq.com/code-breaking/caesar-cipher