Here is a plain text message that hasn't been encrypted at all. You can click the buttons below to shift the alphabet left or right to encrypt this message with a Caesar cipher of your choice. You can also load other encrypted messages and use the tool to see if you can crack the message.
ABCDEFGHIJKLMNOPQRSTUVWXYZOriginal:ABCDEFGHIJKLMNOPQRSTUVWXYZMaps to:Original MessageStandard English

Puzzle 1 of 6

Crack a Caesar cipher!

This tool lets you play with text and do Caesar ciphers. You can use this to either encrypt a message or decrypt it.

Do this

  • Load a Sample message from the message dropdown. This will load a message that has been encrypted with a Caesar cipher.

  • Using the buttons in the Caesar substitution tab, you can shift the alphabet forwards or backwards to try to unscramble the message.

See how long it takes you to crack the cipher! Is this a good method of encrypting secret data?

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