Calculator encrypts entered text by using Vigenère cipher. Non-alphabetic symbols (digits, whitespaces, etc.) are not transformed.

This online calculator tries to decode Vigenère cipher without knowing the key. It uses the index of coincidence technique.

This online calculator performs Kasiski examination of an entered text using trigrams in attempt to discover a key length

This online calculator provides aid in finding Vigenère cipher key if you can guess part of the encrypted text. It just automates some routine calculations, which you would perform manually otherwise.