Tool to decrypt/encrypt with the D3 code. D-3 is a substitution cipher system whose principle is to associate the letter D with the digit 3. D3 is the abbreviation of the french city/word 'Detroit'.
D3 Code - dCode
Tag(s) : Substitution Cipher
dCode is free and its tools are a valuable help in games, maths, geocaching, puzzles and problems to solve every day!
A suggestion ? a feedback ? a bug ? an idea ? Write to dCode!
D3 Code
D3 Decoder
D3 Encoder
Answers to Questions (FAQ)
How to encrypt using D3 cipher?
D-Three Encryption is a particular variant of the A1Z26 (alphabetical rank), but rather than using A=1, the code selects D=3, and the other letters follow the same logic, E=4, F=5 etc.
Example: DCODE is coded 3/2/14/3/4
How to decrypt D3 cipher?
D-3 Decryption associates to each numbers a unique letter (defined during the encryption process according to selected association along with 3=D). (See variants)
How to recognize D3 ciphertext?
A message coded with D3 is composed of numbers, theoretically between 1 and 26, and most probably, the digit 4 of letter E will be more represented.
Any reference to the city of Detroit, Gibraltar, or any strait (détroit in French) is a clue.
What are the variants of the D3 code?
Since D=3 remains invariant, only the way of writing the other letters can change, according to increasing numbers C=2,D=3,E=4 or decreasing C=4,D=3,E=2 even, use negative numbers if necessary (via calculations modulo 26).
Source code
dCode retains ownership of the "D3 Code" source code. Any algorithm for the "D3 Code" algorithm, applet or snippet or script (converter, solver, encryption / decryption, encoding / decoding, ciphering / deciphering, breaker, translator), or any "D3 Code" functions (calculate, convert, solve, decrypt / encrypt, decipher / cipher, decode / encode, translate) written in any informatic language (Python, Java, PHP, C#, Javascript, Matlab, etc.) or any database download or API access for "D3 Code" or any other element are not public (except explicit open source licence). Same with the download for offline use on PC, mobile, tablet, iPhone or Android app.
Reminder: dCode is an educational and teaching resource, accessible online for free and for everyone.
Cite dCode
The content of the page "D3 Code" and its results may be freely copied and reused, including for commercial purposes, provided that dCode.fr is cited as the source (Creative Commons CC-BY free distribution license).
Exporting the results is free and can be done simply by clicking on the export icons ⤓ (.csv or .txt format) or ⧉ (copy and paste).
To cite dCode.fr on another website, use the link:
In a scientific article or book, the recommended bibliographic citation is: D3 Code on dCode.fr [online website], retrieved on 2025-07-15,
