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Vigenère Cipher

Encrypt, decrypt and auto-crack Vigenère ciphers

Tool

Input

Enter plaintext or ciphertext. Leave key empty and use Decrypt + Process to attempt auto-crack.

Text

Key

Output

Quick Examples

One-click examples

Encrypt — Simple

Text: ATTACK AT DAWN · Key: LEMON

Decrypt — Known key

Text: LXFOPV EF RNHR · Key: LEMON

Auto-crack (short)

Text: LXFOPVEFRNHR

Hints

Tips to improve auto-crack

Longer ciphertext improves frequency analysis accuracy.
Try known probable words as key candidates (e.g., LEMON, SECRET).
Use the Quick Auto-crack for a smaller key length search, or Process with empty key for full attempt.