Tool to decrypt/encrypt with a book cipher. The book cipher uses a book as an encryption index, each letter is coded by the rank of a word in the book.
Book Cipher - dCode
Tag(s) : Substitution Cipher
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Book Cipher
Book Cipher Decoder
Book Cipher Encoder
Answers to Questions (FAQ)
How to encrypt using Book cipher?
The Book cipher encryption consists of indexing a text by numbering from 1 to n each word. A letter (or a word) is coded by the number of the word beginning with that same letter (or the whole word).
Choose a well-defined text or book in order to have a precise word list and to facilitate decoding.
Example: Using the Declaration of Independence of the United States of America. To encode DCODE, therefore, the words DISSOLVE,COURSE,ONE,DECENT,EVENTS (with D,C,O,D,E as initials) can be taken (with their respective indexes 15,4,12,52,7) to describe a coded message.
How to decrypt a Book cipher?
Book cipher decryption consists in retrieving the word corresponding to the number and extracting the latter or only its first letter.
Example: For 221,132,136,305 the words are BY,OF,OF,KING or (take the first letters) BOOK.
How are words counted?
Any sequence of 1 to n consecutive letters (or digits) (not interrupted by any other character) is considered as a word.
Example: ALICE'S ADVENTURES IN WONDERLAND contains 5 words: ALICE,S,ADVENTURES,IN,WONDERLAND
How to recognize a Book ciphertext?
The message usually consists of several numbers, from a few tens to sometimes a thousand for the big books (but it is rare because it requires to count up to 1000 words of the book).
All references to books, pages, lines, words, even paper or a library are clues.
Some people call this book substutition ottendorf cipher.
How to decipher a text without the book?
Without knowing the dictionary used it is impossible to decode this cipher.
Also, it is necessary to get along well on the book but also its version, all the printed versions of the same book are not all identical.
What are the variants of the book cipher?
Beale has proposed three cryptograms, one of which (the second one, called the Beale cipher) is coded by this principle. It uses precisely as a dictionary the declaration of independence of the United States of America.
When Book cipher have been invented ?
The first traces of the book cipher are dated from the invention of printing, but could be considered on any paper medium.
Source code
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Cite as source (bibliography):
Book Cipher on dCode.fr [online website], retrieved on 2022-08-08,
