Cipher Identifier

To decrypt / decipher an encoded message, it is necessary to know the encryption used / the encoding method / the cryptographic principle used. Without knowing the technique chosen by the sender of the message, it is impossible to decrypt it. Knowing the encryption / encoding / code is therefore the first step to start the decryption / decoding process.

To recognize the type of encryption / encoding used to encrypt / encode a message, several cryptanalysis methods exist:

- frequency analysis: which characters of the message appear most often? in what proportion? which characters do not appear? This analysis can be carried out for all the characters (but often the letters A-Z and the numbers 0-9 allow to eliminate many methods of ciphers / coding). The analysis of bigrams or trigrams (or more generally group of letters) makes it possible to refine the cryptanalysis, the presence or absence of certain groups of letters are clues.

- the coincidence index: how random are the characters of the message? Intelligible messages (in English) tend to favor certain letters and do not use the E in the same way as the X (much rarer).

- signature search: certain ciphers / encodings have characteristic marks, a signature which makes it identifiable.

Example: The base64 code contains all the possible numbers and letters (upper and lower case) distributed fairly evenly but 3 times out of 4, it ends with the sign =.

When the message is accompanied by clues, certain keywords can trigger results in the dCode search bar, feel free to use it as a complement.

Sometimes finds little or no relevant result, several reasons are possible:

- The message is too short: a message containing not enough characters does not allow a good frequency analysis to be performed. The possibilities become very numerous without a way to precisely identify the encryption.

- The message has a low entropy: it is composed of few distinct characters (a binary message containing only 0s and 1s has a low entropy). Furthermore, nearly all messages can be stored in binary, identifying the encryption precisely is difficult.

- The message is over-encrypted: several successive encodings / ciphers have been applied, the over-encryption tends to mask the characteristic signatures of the original encryption.

- The encryption used is recent: modern cryptography techniques are such that it is impossible to recognize an encrypted message from a random message, it is moreover by this that we recognize a good encryption. Identification is, in essence, difficult.

- The encryption used is very rare: dCode can detect nearly 200 different ciphers and continues to improve thanks to your feedback and messages, but it is not impossible that some ciphers are still missing.

Sometimes the algorithm (based on artificial intelligence and machine learning) tangled up with distinctive cipher signs and returns approximate results. Please contact us with your cipher message, the original message and the encryption method used so that we can teach the analyzer this encryption for future times. The more data there is, the more accurate the detection will be.