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PHP Manual [hash_hmac]

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PHP Manual || Hash Functions

(PHP 5 >= 5.1.2, PHP 7, PECL hash >= 1.1)

hash_hmacGenerate a keyed hash value using the HMAC method


hash_hmac ( string $algo , string $data , string $key [, bool $raw_output = FALSE ] ) : string



Name of selected hashing algorithm (i.e. "md5", "sha256", "haval160,4", etc..) See hash_hmac_algos() for a list of supported algorithms.


Message to be hashed.


Shared secret key used for generating the HMAC variant of the message digest.


When set to TRUE, outputs raw binary data. FALSE outputs lowercase hexits.

Return Values

Returns a string containing the calculated message digest as lowercase hexits unless raw_output is set to true in which case the raw binary representation of the message digest is returned. Returns FALSE when algo is unknown or is a non-cryptographic hash function.


Version Description
7.2.0 Usage of non-cryptographic hash functions (adler32, crc32, crc32b, fnv132, fnv1a32, fnv164, fnv1a64, joaat) was disabled.


Example #1 hash_hmac() example

echo hash_hmac('ripemd160''The quick brown fox jumped over the lazy dog.''secret');

The above example will output:


See Also

  • hash() - Generate a hash value (message digest)
  • hash_hmac_algos() - Return a list of registered hashing algorithms suitable for hash_hmac
  • hash_init() - Initialize an incremental hashing context
  • hash_hmac_file() - Generate a keyed hash value using the HMAC method and the contents of a given file

PHP Manual || Hash Functions