Vigenere Cipher
NewThe Vigenere cipher is a polyalphabetic substitution cipher that uses a keyword to encrypt text. Each letter in the plaintext is shifted by the corresponding letter in the keyword, making it significantly harder to crack than the Caesar cipher. Considered "le chiffre indéchiffrable" (the unbreakable cipher) for centuries until Charles Babbage cracked it in 1854. Used in cryptography education and CTF challenges.
Vigenère Cipher
Polyalphabetic substitution cipher that uses a repeating keyword. Educational tool showing classical cryptography.
For educational purposes only. Not suitable for real data security.
How to Use Vigenere Cipher
- 1Enter the plaintext to encrypt
- 2Enter a keyword (letters only)
- 3View the encrypted ciphertext
- 4Use the same keyword to decrypt
About Vigenere Cipher
The Vigenere cipher is a polyalphabetic substitution cipher that uses a keyword to encrypt text. Each letter in the plaintext is shifted by the corresponding letter in the keyword, making it significantly harder to crack than the Caesar cipher. Considered "le chiffre indéchiffrable" (the unbreakable cipher) for centuries until Charles Babbage cracked it in 1854. Used in cryptography education and CTF challenges.
Your Privacy is Protected
Vigenere Cipher runs entirely in your browser. Your files and data are never uploaded to any server, never stored, and never shared. Everything happens locally on your device using secure browser APIs.
Frequently Asked Questions
How does the Vigenere cipher work?
It uses a repeating keyword. Each plaintext letter is shifted by the alphabetical position of the corresponding keyword letter. For key "KEY": K=10, E=4, Y=24.
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