The ROT13 cipher method uses the Vigenere method, the only difference being that the key should be numeric, so no need to calculate the rank of the letters of the key in the alphabet. The ROT13 cipher method is a variant created by Count ROT13, it is similar to the Vigenere cipher except that it uses just 10 different cipher alphabets, corresponding to the digits 0 to 9.
Eg Plain text : abcdefghi
Key : 123456
Ciphered text : bdfhjlhjl
With our free online tool you can encrypt and decrypt string and password using ROT13 Cipher.