k6/crypto on Grafana Labs

createHash( algorithm )

Mon, 21 Sep 2026 15:16:28 +0000

createHash( algorithm )

Creates a hashing object that can then be fed with data repeatedly, and from which you can extract a hash digest whenever you want.

Parameter	Type	Description
algorithm	string	The name of the hashing algorithm you want to use. Can be any one of “md4”, “md5”, “sha1”, “sha256”, “sha384”, “sha512”, “sha512_224”, “sha512_256”, “ripemd160”.

Returns

Type	Description
object	A Hasher object.

Example

import crypto from 'k6/crypto';

export default function () {
  console.log(crypto.sha256('hello world!', 'hex'));
  const hasher = crypto.createHash('sha256');
  hasher.update('hello ');
  hasher.update('world!');
  console.log(hasher.digest('hex'));
}

The above script should result in the following being printed during execution:

INFO[0000] 7509e5bda0c762d2bac7f90d758b5b2263fa01ccbc542ab5e3df163be08e6ca9
INFO[0000] 7509e5bda0c762d2bac7f90d758b5b2263fa01ccbc542ab5e3df163be08e6ca9

createHMAC( algorithm, secret )

Mon, 21 Sep 2026 15:16:28 +0000

createHMAC( algorithm, secret )

Creates a HMAC hashing object that can then be fed with data repeatedly, and from which you can extract a signed hash digest whenever you want.

Parameter	Type	Description
algorithm	string	The hashing algorithm to use. One of `md4`, `md5`, `sha1`, `sha256`, `sha384`, `sha512`, `sha512_224`, `sha512_256` or `ripemd160`.
secret	string / ArrayBuffer	A shared secret used to sign the data.

Returns

Type	Description
object	A Hasher object.

Example

import crypto from 'k6/crypto';

export default function () {
  console.log(crypto.hmac('sha256', 'a secret', 'my data', 'hex'));
  const hasher = crypto.createHMAC('sha256', 'a secret');
  hasher.update('my ');
  hasher.update('data');
  console.log(hasher.digest('hex'));
}

The above script should result in the following being printed during execution:

INFO[0000] 82f669c8fde13aef6d6977257588dc4953dfac505428f8fd6b52e19cd96d7ea5
INFO[0000] 82f669c8fde13aef6d6977257588dc4953dfac505428f8fd6b52e19cd96d7ea5

hmac( algorithm, secret, data, outputEncoding )

Mon, 21 Sep 2026 15:16:28 +0000

hmac( algorithm, secret, data, outputEncoding )

Use HMAC to sign a piece of data using a shared secret.

Parameter	Type	Description
algorithm	string	The hashing algorithm to use. One of `md4`, `md5`, `sha1`, `sha256`, `sha384`, `sha512`, `sha512_224`, `sha512_256` or `ripemd160`.
secret	string / ArrayBuffer	A shared secret used to sign the data.
data	string / ArrayBuffer	The data to sign.
outputEncoding	string	Describes the type of encoding to use for the hash value. Can be “base64”, “base64url”, “base64rawurl”, “hex” or “binary”.

Returns

Type	Description
string / Array	The hash digest as string (for “base64”, “base64url”, “base64rawurl”, “hex” `outputEncoding`) or raw array of integers (for “binary” `outputEncoding`).

Example

import crypto from 'k6/crypto';

export default function () {
  let hash = crypto.hmac('sha256', 'mysecret', 'hello world!', 'hex');
  console.log(hash);
  const binArray = [104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33];
  hash = crypto.hmac('sha256', 'mysecret', new Uint8Array(binArray).buffer, 'hex');
  console.log(hash);
}

The above script should result in the following being printed during execution:

INFO[0000] 893a72d8cab129e5ba85aea4599fd53f59bfe652cff4098a3780313228d8c20f
INFO[0000] 893a72d8cab129e5ba85aea4599fd53f59bfe652cff4098a3780313228d8c20f

md4( input, outputEncoding )

Mon, 21 Sep 2026 15:16:28 +0000

md4( input, outputEncoding )

Use md4 to hash input data.

Parameter	Type	Description
input	string / ArrayBuffer	The input string or `ArrayBuffer` object to hash.
outputEncoding	string	Describes the type of encoding to use for the hash value. Can be “base64”, “base64url”, “base64rawurl”, “hex” or “binary”.

Returns

Type	Description
string / Array	The hash digest as string (for “base64”, “base64url”, “base64rawurl”, “hex” `outputEncoding`) or raw array of integers (for “binary” `outputEncoding`).

Example

import crypto from 'k6/crypto';

export default function () {
  let hash = crypto.md4('hello world!', 'hex');
  console.log(hash);
  const binArray = [104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33];
  hash = crypto.md4(new Uint8Array(binArray).buffer, 'hex');
  console.log(hash);
}

The above script should result in the following being printed during execution:

INFO[0000] 3363b72840acd5f49f922fef598ee85d
INFO[0000] 3363b72840acd5f49f922fef598ee85d

md5( input, outputEncoding )

Mon, 21 Sep 2026 15:16:28 +0000

md5( input, outputEncoding )

Use md5 to hash input data.

Parameter	Type	Description
input	string / ArrayBuffer	The input string or `ArrayBuffer` object to hash.
outputEncoding	string	Describes the type of encoding to use for the hash value. Can be “base64”, “base64url”, “base64rawurl”, “hex” or “binary”.

Returns

Type	Description
string / Array	The hash digest as string (for “base64”, “base64url”, “base64rawurl”, “hex” `outputEncoding`) or raw array of integers (for “binary” `outputEncoding`).

Example

import crypto from 'k6/crypto';

export default function () {
  let hash = crypto.md5('hello world!', 'hex');
  console.log(hash);
  const binArray = [104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33];
  hash = crypto.md5(new Uint8Array(binArray).buffer, 'hex');
  console.log(hash);
}

The above script should result in the following being printed during execution:

INFO[0000] fc3ff98e8c6a0d3087d515c0473f8677
INFO[0000] fc3ff98e8c6a0d3087d515c0473f8677

randomBytes( int )

Mon, 21 Sep 2026 15:16:28 +0000

randomBytes( int )

Return an ArrayBuffer object with a number of cryptographically random bytes. It will either return exactly the amount of bytes requested or will throw an exception if something went wrong.

Parameter	Type	Description
int	integer	The length of the returned ArrayBuffer.

Returns

Type	Description
ArrayBuffer	An ArrayBuffer with cryptographically random bytes.

Example

import crypto from 'k6/crypto';

export default function () {
  const bytes = crypto.randomBytes(42);
  const view = new Uint8Array(bytes);
  console.log(view); // 156,71,245,191,56,...
}

ripemd160( input, outputEncoding )

Mon, 21 Sep 2026 15:16:28 +0000

ripemd160( input, outputEncoding )

Use ripemd160 to hash input data.

Parameter	Type	Description
input	string / ArrayBuffer	The input string or `ArrayBuffer` object to hash.
outputEncoding	string	Describes the type of encoding to use for the hash value. Can be “base64”, “base64url”, “base64rawurl”, “hex” or “binary”.

Returns

Type	Description
string / Array	The hash digest as string (for “base64”, “base64url”, “base64rawurl”, “hex” `outputEncoding`) or raw array of integers (for “binary” `outputEncoding`).

Example

import crypto from 'k6/crypto';

export default function () {
  let hash = crypto.ripemd160('hello world!', 'hex');
  console.log(hash);
  const binArray = [104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33];
  hash = crypto.ripemd160(new Uint8Array(binArray).buffer, 'hex');
  console.log(hash);
}

The above script should result in the following being printed during execution:

INFO[0000] dffd03137b3a333d5754813399a5f437acd694e5
INFO[0000] dffd03137b3a333d5754813399a5f437acd694e5

sha1( input, outputEncoding )

Mon, 21 Sep 2026 15:16:28 +0000

sha1( input, outputEncoding )

Use sha1 to hash input data.

Parameter	Type	Description
input	string / ArrayBuffer	The input string or `ArrayBuffer` object to hash.
outputEncoding	string	Describes the type of encoding to use for the hash value. Can be “base64”, “base64url”, “base64rawurl”, “hex” or “binary”.

Returns

Type	Description
string / Array	The hash digest as string (for “base64”, “base64url”, “base64rawurl”, “hex” `outputEncoding`) or raw array of integers (for “binary” `outputEncoding`).

Example

import crypto from 'k6/crypto';

export default function () {
  let hash = crypto.sha1('hello world!', 'hex');
  console.log(hash);
  const binArray = [104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33];
  hash = crypto.sha1(new Uint8Array(binArray).buffer, 'hex');
  console.log(hash);
}

The above script should result in the following being printed during execution:

INFO[0000] 430ce34d020724ed75a196dfc2ad67c77772d169
INFO[0000] 430ce34d020724ed75a196dfc2ad67c77772d169

sha256( input, outputEncoding )

Mon, 21 Sep 2026 15:16:28 +0000

sha256( input, outputEncoding )

Use sha256 to hash input data.

Parameter	Type	Description
input	string / ArrayBuffer	The input string or `ArrayBuffer` object to hash.
outputEncoding	string	Describes the type of encoding to use for the hash value. Can be “base64”, “base64url”, “base64rawurl”, “hex” or “binary”.

Returns

Type	Description
string / Array	The hash digest as string (for “base64”, “base64url”, “base64rawurl”, “hex” `outputEncoding`) or raw array of integers (for “binary” `outputEncoding`).

Example

import crypto from 'k6/crypto';

export default function () {
  let hash = crypto.sha256('hello world!', 'hex');
  console.log(hash);
  const binArray = [104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33];
  hash = crypto.sha256(new Uint8Array(binArray).buffer, 'hex');
  console.log(hash);
}

The above script should result in the following being printed during execution:

INFO[0000] 7509e5bda0c762d2bac7f90d758b5b2263fa01ccbc542ab5e3df163be08e6ca9
INFO[0000] 7509e5bda0c762d2bac7f90d758b5b2263fa01ccbc542ab5e3df163be08e6ca9

sha384( input, outputEncoding )

Mon, 21 Sep 2026 15:16:28 +0000

sha384( input, outputEncoding )

Use sha384 to hash input data.

Parameter	Type	Description
input	string / ArrayBuffer	The input string or `ArrayBuffer` object to hash.
outputEncoding	string	Describes the type of encoding to use for the hash value. Can be “base64”, “base64url”, “base64rawurl”, “hex” or “binary”.

Returns

Type	Description
string / Array	The hash digest as string (for “base64”, “base64url”, “base64rawurl”, “hex” `outputEncoding`) or raw array of integers (for “binary” `outputEncoding`).

Example

import crypto from 'k6/crypto';

export default function () {
  let hash = crypto.sha384('hello world!', 'hex');
  console.log(hash);
  const binArray = [104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33];
  hash = crypto.sha384(new Uint8Array(binArray).buffer, 'hex');
  console.log(hash);
}

The above script should result in the following being printed during execution:

INFO[0000] d33d40f7010ce34aa86efd353630309ed5c3d7ffac66d988825cf699f4803ccdf3f033230612f0945332fb580d8af805
INFO[0000] d33d40f7010ce34aa86efd353630309ed5c3d7ffac66d988825cf699f4803ccdf3f033230612f0945332fb580d8af805

sha512( input, outputEncoding )

Mon, 21 Sep 2026 15:16:28 +0000

sha512( input, outputEncoding )

Use sha512 to hash input data.

Parameter	Type	Description
input	string / ArrayBuffer	The input string or `ArrayBuffer` object to hash.
outputEncoding	string	Describes the type of encoding to use for the hash value. Can be “base64”, “base64url”, “base64rawurl”, “hex” or “binary”.

Returns

Type	Description
string / Array	The hash digest as string (for “base64”, “base64url”, “base64rawurl”, “hex” `outputEncoding`) or raw array of integers (for “binary” `outputEncoding`).

Example

import crypto from 'k6/crypto';

export default function () {
  let hash = crypto.sha512('hello world!', 'hex');
  console.log(hash);
  const binArray = [104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33];
  hash = crypto.sha512(new Uint8Array(binArray).buffer, 'hex');
  console.log(hash);
}

The above script should result in the following being printed during execution:

INFO[0000] db9b1cd3262dee37756a09b9064973589847caa8e53d31a9d142ea2701b1b28abd97838bb9a27068ba305dc8d04a45a1fcf079de54d607666996b3cc54f6b67c
INFO[0000] db9b1cd3262dee37756a09b9064973589847caa8e53d31a9d142ea2701b1b28abd97838bb9a27068ba305dc8d04a45a1fcf079de54d607666996b3cc54f6b67c

sha512_256( input, outputEncoding )

Mon, 21 Sep 2026 15:16:28 +0000

sha512_256( input, outputEncoding )

Use sha512_256 to hash input data.

Parameter	Type	Description
input	string / ArrayBuffer	The input string or `ArrayBuffer` object to hash.
outputEncoding	string	Describes the type of encoding to use for the hash value. Can be “base64”, “base64url”, “base64rawurl”, “hex” or “binary”.

Returns

Type	Description
string / Array	The hash digest as string (for “base64”, “base64url”, “base64rawurl”, “hex” `outputEncoding`) or raw array of integers (for “binary” `outputEncoding`).

Example

import crypto from 'k6/crypto';

export default function () {
  let hash = crypto.sha512_256('hello world!', 'hex');
  console.log(hash);
  const binArray = [104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33];
  hash = crypto.sha512_256(new Uint8Array(binArray).buffer, 'hex');
  console.log(hash);
}

The above script should result in the following being printed during execution:

INFO[0000] 595b5926068b4828fb1c27db21281e31118b8475cb6c3ceeb09be7b685414d5f
INFO[0000] 595b5926068b4828fb1c27db21281e31118b8475cb6c3ceeb09be7b685414d5f

sha512_224( input, outputEncoding )

Mon, 21 Sep 2026 15:16:28 +0000

sha512_224( input, outputEncoding )

Use sha512_224 to hash input data.

Parameter	Type	Description
input	string / ArrayBuffer	The input string or `ArrayBuffer` object to hash.
outputEncoding	string	Describes the type of encoding to use for the hash value. Can be “base64”, “base64url”, “base64rawurl”, “hex” or “binary”.

Returns

Type	Description
string / Array	The hash digest as string (for “base64”, “base64url”, “base64rawurl”, “hex” `outputEncoding`) or raw array of integers (for “binary” `outputEncoding`).

Example

import crypto from 'k6/crypto';

export default function () {
  let hash = crypto.sha512_224('hello world!', 'hex');
  console.log(hash);
  const binArray = [104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 33];
  hash = crypto.sha512_224(new Uint8Array(binArray).buffer, 'hex');
  console.log(hash);
}

The above script should result in the following being printed during execution:

INFO[0000] bc4ed196f7ba1c20f6fb6be1f91edf8293a35b065d6e7d6fd368c890
INFO[0000] bc4ed196f7ba1c20f6fb6be1f91edf8293a35b065d6e7d6fd368c890

Hasher

Mon, 21 Sep 2026 15:16:28 +0000

Hasher

This object is returned by crypto.createHash() and allows the user to successively add more string data to be hashed, and to extract digests along the way.

Name	Type	Description
Hasher.update(string)	function	Add more data to the string we want to create a hash of. Takes one string argument, which is the new data we want to add.
Hasher.digest(string)	function	Return a digest from the data added (using `update()`) to the Hasher object so far. Takes one string argument, which is the encoding format to return. This can be either “base64”, “base64url”, “base64rawurl”, “hex” or “binary”. See the examples below for details.

Example

import crypto from 'k6/crypto';

export default function () {
  console.log(crypto.sha256('hello world!', 'hex'));
  const hasher = crypto.createHash('sha256');
  hasher.update('hello ');
  hasher.update('world!');
  console.log(hasher.digest('hex'));

  // Other encodings
  console.log('base64:', hasher.digest('base64'));
  console.log('base64url:', hasher.digest('base64url'));
  console.log('base64rawurl:', hasher.digest('base64rawurl'));
  console.log('binary:', new Uint8Array(hasher.digest('binary')));
}

The above code sample should produce this in its output:

INFO[0000] 7509e5bda0c762d2bac7f90d758b5b2263fa01ccbc542ab5e3df163be08e6ca9
INFO[0000] 7509e5bda0c762d2bac7f90d758b5b2263fa01ccbc542ab5e3df163be08e6ca9
INFO[0000] base64: dQnlvaDHYtK6x/kNdYtbImP6Acy8VCq1498WO+CObKk=
INFO[0000] base64url: dQnlvaDHYtK6x_kNdYtbImP6Acy8VCq1498WO-CObKk=
INFO[0000] base64rawurl: dQnlvaDHYtK6x_kNdYtbImP6Acy8VCq1498WO-CObKk
INFO[0000] binary: 117,9,229,189,160,199,98,210,186,199,249,13,117,139,91,34,99,250,1,204,188,84,42,181,227,223,22,59,224,142,108,169