Tool to decrypt/encrypt with T9 mode for SMS messages on mobile phone. T9 (Text on 9 keys) is a predictive text method based on a dictionary, used in mobile phones to type text on a keyboard with only numeric keys. Less and less used, T9 can be used to easily cipher messages.
T9 Cipher (SMS) - dCode
Tag(s) : Telecom, Substitution Cipher
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T9 Cipher (SMS)
T9 Decoder/Phonewords Finder
T9 Encoder
Textonym list
Tool to decrypt/encrypt with T9 mode for SMS messages on mobile phone. T9 (Text on 9 keys) is a predictive text method based on a dictionary, used in mobile phones to type text on a keyboard with only numeric keys. Less and less used, T9 can be used to easily cipher messages.
Answers to Questions
How to encrypt using T9 cipher?
T9 encryption replaces a letter by the corresponding key code on a mobile phone keypad (compatible with Text on 9 keys).
Example: DCODE becomes 32633
Do not confuse the T9 with the multi-tap code (successively press the keys until you get the correct letter)
How to decrypt T9 cipher?
The decryption of the T9 is normally based on a dictionary where all the words have been previously encoded.
It is normally impossible to write a word that does not exist but the dCode T9 translator in brute-force mode will test all the possibilities of words.
Example: 22 = AA,AB,AC,BA,BB,BC,CA,CB,CC
This functionality allows creating phonewords (especially if the phone number avoids digits 0 and 1)
How to recognize T9 ciphertext?
The ciphered message is made of digits, if there are 1 or 0, these digits can only code spaces or punctuation.
What are the variants of the T9 cipher?
Mobile phones have other typing techniques, such as Multi-tap code (ABC mode). With the same keyboard, DCODE is written 3222666333.
What is a Textonym?
A textonym is the name given to each word written in the same manner in T9.
COOL = 2665 = BOOK
Textonym list
Make proposals!
When T9 have been invented ?
Patent is from 1985
Source code
dCode retains ownership of the source code of the script T9 Cipher (SMS) online. Except explicit open source licence (indicated Creative Commons / free), any algorithm, applet, snippet, software (converter, solver, encryption / decryption, encoding / decoding, ciphering / deciphering, translator), or any function (convert, solve, decrypt, encrypt, decipher, cipher, decode, code, translate) written in any informatic langauge (PHP, Java, C#, Python, Javascript, Matlab, etc.) which dCode owns rights will not be released for free. To download the online T9 Cipher (SMS) script for offline use on PC, iPhone or Android, ask for price quote on contact page !
Questions / Comments
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