Rot13 Encrypt and Decrypt

Rot13 decrypt or encrypt text using the textarea below. Rot13 is its own inverse, which means that the same function that encrypts the text will also decrypt the text, which is why this form has only one button to apply the cypher, rather than one for encoding and one for decoding.

What is Rot13 Enoding?

Rot13 is an example of a simple Caesar cipher, where every character in a piece of text is shifted down a fixed number of positions in the alphabet. For example, a shift of one would mean all B’s in a text would be replaced with A’s. When you reach the bottom of the alphabet, you wrap around to the top, so in this case, A’s would become Z’s.

Rot13 is just a Caesar cipher with a shift of 13, and is short for “Rotate 13”. There is something special about choosing 13 as your shift, and that’s because the Latin alphabet has 26 characters. This means that applying Rot13 twice in a row will give you back the original text.

What is Rot13 used for?

Rot13 is both simple and well known, and thus provides essentially no real security. This doesn’t mean it isn’t useful. It’s hard to read and simple to decode, which makes it perfect for things like hiding movie spoilers or solutions to exercises.

Rot13 Lookup Table

ABCDEFGHIJKLMNOPQRSTUVWXYZ
NOPQRSTUVWXYZABCDEFGHIJKLM


abcdefghijklmnopqrstuvwxyz
nopqrstuvwxyzabcdefghijklm

Rot13 in Vim

Strangely enough, Vim has built in support for applying the Rot13 cipher with the g? command.

To Rot13 encode an entire file in vim run the following command with your cursor at the beginning of the file: g?G