ROT13 & Caesar Cipher
Shift letters around the alphabet: ROT13, or any Caesar shift from 1 to 25.
Shifted
Examples
Questions
Why does ROT13 undo itself?
The alphabet has 26 letters, and 13 is half of that. Shifting by 13 twice goes all the way round, so encoding and decoding are the same step.
What is a Caesar cipher?
Each letter moves a fixed number of places along the alphabet. Julius Caesar is said to have used a shift of 3, so A became D. ROT13 is the same idea with a shift of 13.
How do I decode a message when I don't know the shift?
Tick "Show all 25 shifts" and look for the line that reads as words. There are only 25 possible keys, which is why a Caesar cipher is not real encryption.
What happens to numbers, accents and emoji?
They stay as they are. Only the letters A to Z (either case) are shifted, unless you tick "Shift digits too".
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