Caesar Cipher
The Caesar cipher is a simple scheme that shifts every letter of the alphabet by a fixed amount. With a shift of 3, A → D and B → E. This page uses the 26 letters of the English alphabet.
In the 1st century BC the Roman general Julius Caesar used this method to hide his military correspondence. Even if an enemy intercepted a message, they met nothing but meaningless letters — without knowing the shift, the text cannot be read.
Today the Caesar cipher is not considered secure on its own: with only 26 possible shifts, trial and error breaks it in moments. But it is a perfect starting point for understanding the foundations of modern cryptography.
1
Encrypt
Only English letters and spaces are accepted (punctuation cannot be entered).
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