Tool to decrypt/encrypt with a cardan grille. The Cardan grille is a mask superimposed to the text that bring up some letters to make a message.
Cardan Grille - dCode
Tag(s) : Substitution Cipher
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Cardan Grille
Cardan Grille Decoder
Cardan Grille Encoder
Answers to Questions (FAQ)
How to encrypt using Cardan Grille cipher?
Cardan encryption uses another text (understandable or not) of which only a few letters are from the original text.
In practice, Cardan uses a mask, a grille in which some cells are opaque, others empty.
Example: Code DCODE with the mask XXXXXX_XXXXXX_XXX_X_XXXXX_XXXX where X is an opaque cell and _ an empty one.
Superimpose the mask cover, write the text in the empty boxes, remove this cover and fill the rest with random letters.
Example: DCODE is written in empty cells XXXXXXDXXXXXXCXXXOXDXXXXXEXXXX and it is possible to fill with letters like OZPCESDVIDGABCNTEOHDERXJXEMLUE
How to decrypt Cardan Grille cipher?
Cardan decryption requires knowledge of the grille. The decrypted text appears by placing the cover on the text.
Example:
| OESDVBCNEOHDEEML |
| XXX_XX_XX_X_X_XX |
| XXXDXXCXXOXDXEXX |
| ___D__C__O_D_E__ |
How to recognize Cardan Grille ciphertext?
The encrypted message is very long compared to original plain text.
Cardinal Richelieu encrypted his messages in the same way, but the ciphertext took the classical form of a common text. The secret message consisted of only a few of the letters of the message that were revealed with the cache. Any reference to Cardinal Richelieu can be a clue.
How to decipher Cardan Grille without the grille?
The decryption without grille is very difficult, one should try all the grids.
Using a probable word, it is possible to estimate the coverage mask and know the amount of letters to ignore.
Why the Cardan name?
Cardan is the name of Jérome Cardan (Gerolamo Cardano) its italian creator.
Source code
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