SHA1 Decrypter - Password (+Salt) SHA-1 Hash - Online Decoder/Encoder (2024)

The SHA-1 hash (for Secure Hash Algorithm) is a hashing algorithm providing a hash of 40 hexadecimal characters.

Reminder: hashing is a technique which, from a starting chain, provides a unique fingerprint, making it possible to identify the initial data and guarantee its integrity.

Encryption calculates a numeric footprint of 40 hexadecimal characters. The algorithm uses non linear functions, here are the 3 main ones:

$$ C(x,y,z) = (x \wedge y) \vee (\lnot x \wedge z) \\ P(x,y,z) = x \oplus y \oplus z \\ M(x,y,z) = (x \wedge y) \vee (x \wedge z) $$

With $ x,y,z $ portions of string to encode or fixed values among 0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476, 0xC3D2E1F0 (and others)

Example: dCode is encrypted with the footprint 15fc6eed5ed024bfb86c4130f998dde437f528ee.

As encryption is a hashing based on nonlinear functions, there is no decryption method. This means that to retrieve the password corresponding to a sha-1 hash, there is no choice but to try all possible passwords!

Technically, this operation would take several thousand years, even on the most powerful computers in the world. However, the list of passwords used in real life is more restricted, and it becomes possible to precalculate the most likely fingerprints.

dCode uses its word databases (10 million potential passwords) to speed up this processing. However, if the password is rare, or combined with salting, it will probably not be found.

The database search can be complicated by inserting a salt to the word. The salt is usually a prefix or a suffix. Indeed, if it is already difficult but possible to precalculate the fingerprints of all the words, it becomes even more difficult to precalculate with all possible prefixes and suffixes.

Example: SHA1(dCode) = 15fc6eed5ed024bfb86c4130f998dde437f528ee but SHA1(dCodeSUFFIX) = 9b63fcb31388acee8879018244a3d107033890f1

Another (not recommended) variant is DOUBLE SHA1, that consists in applying SHA1 twice (the first time on the original string, then the second time on the computed hash).

List of magic SHA-1 hashes:

Bonus magic SHA-1 like string that can also be evaluated at 0: 0e00000000000000000000081614617300000000 or 0e00000000000000000000721902017120000000

SHA1 stands for Secure Hash Algorithm (version 1)