hash

Converts a string into a fixed length hexadecimal string.

NOTE: The result is useful for comparison and validation, such as storing and validating a hashed password without exposing the original password.

hash(string [, algorithm [, encoding]] [, additionalIterations]) → returns string

Argument Reference

string string
Required

algorithm string
Default: `MD5`

CF 7+ A supported algorithm such as MD5,SHA,SHA-256,SHA-384, or SHA-512. Of those listed SHA-512 is the strongest and generates a 128 character hex result.

NOTE: The Enterprise Edition of ColdFusion installs the RSA BSafe Crypto-J library, which provides FIPS-140 Compliant Strong Cryptography. This includes additional algorithms. You can also install additional cryptography algorithms and use those hashing algorithms.

Values:

CFMX_COMPAT
MD5
SHA
SHA-256
SHA-384
SHA-512

encoding string
Default: `UTF-8`

CF 7+ A string specifying the encoding to use when converting the string to byte data used by the hash algorithm.
Must be a character encoding name recognized by the Java runtime.

NOTE: The default is specified by the value of defaultCharset in the neo-runtime.xml file, which is normally UTF-8.
NOTE: This is ignored when using the CFMX_COMPAT algorithm.

Values:

utf-8
iso-8859-1
windows-1252
us-ascii
shift_jis
iso-2022-jp
euc-jp
euc-kr
big5
euc-cn
utf-16

additionalIterations numeric
Default: `0`

CF 10+ Iterates the number of times the hash is computed to create a more computationally intensive hash. Lucee and Adobe CF implement this differently (off by one), see compatibility notes below.

NOTE: This parameter appears to be ignored if the CFMX_COMPAT default algorithm is used.

Compatibility

ColdFusion:

Version 4.5+ CF7 added additional algorithm support, CF10 added the iterations option. CF2018 uses additionalIterations as the iterations param.

Lucee:

The iterations value represents the total number of hashes on Lucee, in Adobe CF the value is the number of additional iterations. In Lucee5+, the iterations param is numIterations.

Links more information about hash

Hashing Byte Arrays - Tutorial style article on using the hash function in CFML.

Examples
Sample code invoking the hash function

SHA-256 Hash Example

Returns 64 character hex result.

hash("something", "SHA-256", "UTF-8")

Expected Result: 3FC9B689459D738F8C88A3A48AA9E33542016B7A4052E001AAA536FCA74813CB

MD5 Hash Example

MD5 is not recommended for use requiring security.

hash("something")

Expected Result: 437B930DB84B8079C2DD804A71936B5F