Web Crypto API

Stability: 1 - Experimental

Node.js provides an implementation of the standard Web Crypto API.

Use require('node:crypto').webcrypto to access this module.

const { subtle } = require('node:crypto').webcrypto;

(async function() {

  const key = await subtle.generateKey({
    name: 'HMAC',
    hash: 'SHA-256',
    length: 256
  }, true, ['sign', 'verify']);

  const enc = new TextEncoder();
  const message = enc.encode('I love cupcakes');

  const digest = await subtle.sign({
    name: 'HMAC'
  }, key, message);

})();

Examples

Generating keys

The {SubtleCrypto} class can be used to generate symmetric (secret) keys or asymmetric key pairs (public key and private key).

AES keys

const { subtle } = require('node:crypto').webcrypto;

async function generateAesKey(length = 256) {
  const key = await subtle.generateKey({
    name: 'AES-CBC',
    length
  }, true, ['encrypt', 'decrypt']);

  return key;
}

ECDSA key pairs

const { subtle } = require('node:crypto').webcrypto;

async function generateEcKey(namedCurve = 'P-521') {
  const {
    publicKey,
    privateKey
  } = await subtle.generateKey({
    name: 'ECDSA',
    namedCurve,
  }, true, ['sign', 'verify']);

  return { publicKey, privateKey };
}

Ed25519/Ed448/X25519/X448 key pairs

Stability: 1 - Experimental

const { subtle } = require('node:crypto').webcrypto;

async function generateEd25519Key() {
  return subtle.generateKey({
    name: 'Ed25519',
  }, true, ['sign', 'verify']);
}

async function generateX25519Key() {
  return subtle.generateKey({
    name: 'X25519',
  }, true, ['deriveKey']);
}

HMAC keys

const { subtle } = require('node:crypto').webcrypto;

async function generateHmacKey(hash = 'SHA-256') {
  const key = await subtle.generateKey({
    name: 'HMAC',
    hash
  }, true, ['sign', 'verify']);

  return key;
}

RSA key pairs

const { subtle } = require('node:crypto').webcrypto;
const publicExponent = new Uint8Array([1, 0, 1]);

async function generateRsaKey(modulusLength = 2048, hash = 'SHA-256') {
  const {
    publicKey,
    privateKey
  } = await subtle.generateKey({
    name: 'RSASSA-PKCS1-v1_5',
    modulusLength,
    publicExponent,
    hash,
  }, true, ['sign', 'verify']);

  return { publicKey, privateKey };
}

Encryption and decryption

const crypto = require('node:crypto').webcrypto;

async function aesEncrypt(plaintext) {
  const ec = new TextEncoder();
  const key = await generateAesKey();
  const iv = crypto.getRandomValues(new Uint8Array(16));

  const ciphertext = await crypto.subtle.encrypt({
    name: 'AES-CBC',
    iv,
  }, key, ec.encode(plaintext));

  return {
    key,
    iv,
    ciphertext
  };
}

async function aesDecrypt(ciphertext, key, iv) {
  const dec = new TextDecoder();
  const plaintext = await crypto.subtle.decrypt({
    name: 'AES-CBC',
    iv,
  }, key, ciphertext);

  return dec.decode(plaintext);
}

Exporting and importing keys

const { subtle } = require('node:crypto').webcrypto;

async function generateAndExportHmacKey(format = 'jwk', hash = 'SHA-512') {
  const key = await subtle.generateKey({
    name: 'HMAC',
    hash
  }, true, ['sign', 'verify']);

  return subtle.exportKey(format, key);
}

async function importHmacKey(keyData, format = 'jwk', hash = 'SHA-512') {
  const key = await subtle.importKey(format, keyData, {
    name: 'HMAC',
    hash
  }, true, ['sign', 'verify']);

  return key;
}

Wrapping and unwrapping keys

const { subtle } = require('node:crypto').webcrypto;

async function generateAndWrapHmacKey(format = 'jwk', hash = 'SHA-512') {
  const [
    key,
    wrappingKey,
  ] = await Promise.all([
    subtle.generateKey({
      name: 'HMAC', hash
    }, true, ['sign', 'verify']),
    subtle.generateKey({
      name: 'AES-KW',
      length: 256
    }, true, ['wrapKey', 'unwrapKey']),
  ]);

  const wrappedKey = await subtle.wrapKey(format, key, wrappingKey, 'AES-KW');

  return { wrappedKey, wrappingKey };
}

async function unwrapHmacKey(
  wrappedKey,
  wrappingKey,
  format = 'jwk',
  hash = 'SHA-512') {

  const key = await subtle.unwrapKey(
    format,
    wrappedKey,
    wrappingKey,
    'AES-KW',
    { name: 'HMAC', hash },
    true,
    ['sign', 'verify']);

  return key;
}

Sign and verify

const { subtle } = require('node:crypto').webcrypto;

async function sign(key, data) {
  const ec = new TextEncoder();
  const signature =
    await subtle.sign('RSASSA-PKCS1-v1_5', key, ec.encode(data));
  return signature;
}

async function verify(key, signature, data) {
  const ec = new TextEncoder();
  const verified =
    await subtle.verify(
      'RSASSA-PKCS1-v1_5',
      key,
      signature,
      ec.encode(data));
  return verified;
}

Deriving bits and keys

const { subtle } = require('node:crypto').webcrypto;

async function pbkdf2(pass, salt, iterations = 1000, length = 256) {
  const ec = new TextEncoder();
  const key = await subtle.importKey(
    'raw',
    ec.encode(pass),
    'PBKDF2',
    false,
    ['deriveBits']);
  const bits = await subtle.deriveBits({
    name: 'PBKDF2',
    hash: 'SHA-512',
    salt: ec.encode(salt),
    iterations
  }, key, length);
  return bits;
}

async function pbkdf2Key(pass, salt, iterations = 1000, length = 256) {
  const ec = new TextEncoder();
  const keyMaterial = await subtle.importKey(
    'raw',
    ec.encode(pass),
    'PBKDF2',
    false,
    ['deriveKey']);
  const key = await subtle.deriveKey({
    name: 'PBKDF2',
    hash: 'SHA-512',
    salt: ec.encode(salt),
    iterations
  }, keyMaterial, {
    name: 'AES-GCM',
    length: 256
  }, true, ['encrypt', 'decrypt']);
  return key;
}

Digest

const { subtle } = require('node:crypto').webcrypto;

async function digest(data, algorithm = 'SHA-512') {
  const ec = new TextEncoder();
  const digest = await subtle.digest(algorithm, ec.encode(data));
  return digest;
}

Algorithm matrix

The table details the algorithms supported by the Node.js Web Crypto API implementation and the APIs supported for each:

Algorithm	`generateKey`	`exportKey`	`importKey`	`encrypt`	`decrypt`	`wrapKey`	`unwrapKey`	`deriveBits`	`deriveKey`	`sign`	`verify`	`digest`
`'RSASSA-PKCS1-v1_5'`	✔	✔	✔							✔	✔
`'RSA-PSS'`	✔	✔	✔							✔	✔
`'RSA-OAEP'`	✔	✔	✔	✔	✔	✔	✔
`'ECDSA'`	✔	✔	✔							✔	✔
`'Ed25519'`[^1]	✔	✔	✔							✔	✔
`'Ed448'`[^1]	✔	✔	✔							✔	✔
`'ECDH'`	✔	✔	✔					✔	✔
`'X25519'`[^1]	✔	✔	✔					✔	✔
`'X448'`[^1]	✔	✔	✔					✔	✔
`'AES-CTR'`	✔	✔	✔	✔	✔	✔	✔
`'AES-CBC'`	✔	✔	✔	✔	✔	✔	✔
`'AES-GCM'`	✔	✔	✔	✔	✔	✔	✔
`'AES-KW'`	✔	✔	✔			✔	✔
`'HMAC'`	✔	✔	✔							✔	✔
`'HKDF'`		✔	✔					✔	✔
`'PBKDF2'`		✔	✔					✔	✔
`'SHA-1'`												✔
`'SHA-256'`												✔
`'SHA-384'`												✔
`'SHA-512'`												✔

Class: `Crypto`

Calling require('node:crypto').webcrypto returns an instance of the Crypto class. Crypto is a singleton that provides access to the remainder of the crypto API.

`crypto.subtle`

Type: {SubtleCrypto}

Provides access to the SubtleCrypto API.

`crypto.getRandomValues(typedArray)`

typedArray {Buffer|TypedArray}
Returns: {Buffer|TypedArray}

Generates cryptographically strong random values. The given typedArray is filled with random values, and a reference to typedArray is returned.

The given typedArray must be an integer-based instance of {TypedArray}, i.e. Float32Array and Float64Array are not accepted.

An error will be thrown if the given typedArray is larger than 65,536 bytes.

`crypto.randomUUID()`

Returns: {string}

Generates a random RFC 4122 version 4 UUID. The UUID is generated using a cryptographic pseudorandom number generator.

Class: `CryptoKey`

`cryptoKey.algorithm`

Type: {AesKeyGenParams|RsaHashedKeyGenParams|EcKeyGenParams|HmacKeyGenParams}

An object detailing the algorithm for which the key can be used along with additional algorithm-specific parameters.

Read-only.

`cryptoKey.extractable`

Type: {boolean}

When true, the {CryptoKey} can be extracted using either subtleCrypto.exportKey() or subtleCrypto.wrapKey().

Read-only.

`cryptoKey.type`

Type: {string} One of 'secret', 'private', or 'public'.

A string identifying whether the key is a symmetric ('secret') or asymmetric ('private' or 'public') key.

`cryptoKey.usages`

Type: {string[]}

An array of strings identifying the operations for which the key may be used.

The possible usages are:

'encrypt' - The key may be used to encrypt data.
'decrypt' - The key may be used to decrypt data.
'sign' - The key may be used to generate digital signatures.
'verify' - The key may be used to verify digital signatures.
'deriveKey' - The key may be used to derive a new key.
'deriveBits' - The key may be used to derive bits.
'wrapKey' - The key may be used to wrap another key.
'unwrapKey' - The key may be used to unwrap another key.

Valid key usages depend on the key algorithm (identified by cryptokey.algorithm.name).

Key Type	`'encrypt'`	`'decrypt'`	`'sign'`	`'verify'`	`'deriveKey'`	`'deriveBits'`	`'wrapKey'`	`'unwrapKey'`
`'AES-CBC'`	✔	✔					✔	✔
`'AES-CTR'`	✔	✔					✔	✔
`'AES-GCM'`	✔	✔					✔	✔
`'AES-KW'`							✔	✔
`'ECDH'`					✔	✔
`'X25519'`[^1]					✔	✔
`'X448'`[^1]					✔	✔
`'ECDSA'`			✔	✔
`'Ed25519'`[^1]			✔	✔
`'Ed448'`[^1]			✔	✔
`'HDKF'`					✔	✔
`'HMAC'`			✔	✔
`'PBKDF2'`					✔	✔
`'RSA-OAEP'`	✔	✔					✔	✔
`'RSA-PSS'`			✔	✔
`'RSASSA-PKCS1-v1_5'`			✔	✔

Class: `CryptoKeyPair`

The CryptoKeyPair is a simple dictionary object with publicKey and privateKey properties, representing an asymmetric key pair.

`cryptoKeyPair.privateKey`

Type: {CryptoKey} A {CryptoKey} whose type will be 'private'.

`cryptoKeyPair.publicKey`

Type: {CryptoKey} A {CryptoKey} whose type will be 'public'.

Class: `SubtleCrypto`

`subtle.decrypt(algorithm, key, data)`

algorithm: {RsaOaepParams|AesCtrParams|AesCbcParams|AesGcmParams}
key: {CryptoKey}
data: {ArrayBuffer|TypedArray|DataView|Buffer}
Returns: {Promise} containing {ArrayBuffer}

Using the method and parameters specified in algorithm and the keying material provided by key, subtle.decrypt() attempts to decipher the provided data. If successful, the returned promise will be resolved with an {ArrayBuffer} containing the plaintext result.

The algorithms currently supported include:

'RSA-OAEP'
'AES-CTR'
'AES-CBC'
'AES-GCM'

`subtle.deriveBits(algorithm, baseKey, length)`

algorithm: {AlgorithmIdentifier|EcdhKeyDeriveParams|HkdfParams|Pbkdf2Params}
baseKey: {CryptoKey}
length: {number}
Returns: {Promise} containing {ArrayBuffer}

Using the method and parameters specified in algorithm and the keying material provided by baseKey, subtle.deriveBits() attempts to generate length bits. The Node.js implementation requires that length is a multiple of 8. If successful, the returned promise will be resolved with an {ArrayBuffer} containing the generated data.

The algorithms currently supported include:

'ECDH'
'HKDF'
'PBKDF2'

`subtle.deriveKey(algorithm, baseKey, derivedKeyAlgorithm, extractable, keyUsages)`

algorithm: {AlgorithmIdentifier|EcdhKeyDeriveParams|HkdfParams|Pbkdf2Params}
baseKey: {CryptoKey}
derivedKeyAlgorithm: {HmacKeyGenParams|AesKeyGenParams}
extractable: {boolean}
keyUsages: {string[]} See Key usages.
Returns: {Promise} containing {CryptoKey}

Using the method and parameters specified in algorithm, and the keying material provided by baseKey, subtle.deriveKey() attempts to generate a new {CryptoKey} based on the method and parameters in derivedKeyAlgorithm.

Calling subtle.deriveKey() is equivalent to calling subtle.deriveBits() to generate raw keying material, then passing the result into the subtle.importKey() method using the deriveKeyAlgorithm, extractable, and keyUsages parameters as input.

The algorithms currently supported include:

'ECDH'
'HKDF'
'PBKDF2'

`subtle.digest(algorithm, data)`

algorithm: {string|Object}
data: {ArrayBuffer|TypedArray|DataView|Buffer}
Returns: {Promise} containing {ArrayBuffer}

Using the method identified by algorithm, subtle.digest() attempts to generate a digest of data. If successful, the returned promise is resolved with an {ArrayBuffer} containing the computed digest.

If algorithm is provided as a {string}, it must be one of:

'SHA-1'
'SHA-256'
'SHA-384'
'SHA-512'

If algorithm is provided as an {Object}, it must have a name property whose value is one of the above.

`subtle.encrypt(algorithm, key, data)`

algorithm: {RsaOaepParams|AesCtrParams|AesCbcParams|AesGcmParams}
key: {CryptoKey}
Returns: {Promise} containing {ArrayBuffer}

Using the method and parameters specified by algorithm and the keying material provided by key, subtle.encrypt() attempts to encipher data. If successful, the returned promise is resolved with an {ArrayBuffer} containing the encrypted result.

The algorithms currently supported include:

'RSA-OAEP'
'AES-CTR'
'AES-CBC'
'AES-GCM'

`subtle.exportKey(format, key)`

format: {string} Must be one of 'raw', 'pkcs8', 'spki', or 'jwk'.
key: {CryptoKey}
Returns: {Promise} containing {ArrayBuffer}.

Exports the given key into the specified format, if supported.

If the {CryptoKey} is not extractable, the returned promise will reject.

When format is either 'pkcs8' or 'spki' and the export is successful, the returned promise will be resolved with an {ArrayBuffer} containing the exported key data.

When format is 'jwk' and the export is successful, the returned promise will be resolved with a JavaScript object conforming to the JSON Web Key specification.

Key Type	`'spki'`	`'pkcs8'`	`'jwk'`	`'raw'`
`'AES-CBC'`			✔	✔
`'AES-CTR'`			✔	✔
`'AES-GCM'`			✔	✔
`'AES-KW'`			✔	✔
`'ECDH'`	✔	✔	✔	✔
`'ECDSA'`	✔	✔	✔	✔
`'Ed25519'`[^1]	✔	✔	✔	✔
`'Ed448'`[^1]	✔	✔	✔	✔
`'HDKF'`
`'HMAC'`			✔	✔
`'PBKDF2'`
`'RSA-OAEP'`	✔	✔	✔
`'RSA-PSS'`	✔	✔	✔
`'RSASSA-PKCS1-v1_5'`	✔	✔	✔

`subtle.generateKey(algorithm, extractable, keyUsages)`

algorithm: {AlgorithmIdentifier|RsaHashedKeyGenParams|EcKeyGenParams|HmacKeyGenParams|AesKeyGenParams}

extractable: {boolean}
keyUsages: {string[]} See Key usages.
Returns: {Promise} containing {CryptoKey|CryptoKeyPair}

Using the method and parameters provided in algorithm, subtle.generateKey() attempts to generate new keying material. Depending the method used, the method may generate either a single {CryptoKey} or a {CryptoKeyPair}.

The {CryptoKeyPair} (public and private key) generating algorithms supported include:

'RSASSA-PKCS1-v1_5'
'RSA-PSS'
'RSA-OAEP'
'ECDSA'
'Ed25519'[^1]
'Ed448'[^1]
'ECDH'
'X25519'[^1]
'X448'[^1]

The {CryptoKey} (secret key) generating algorithms supported include:

'HMAC'
'AES-CTR'
'AES-CBC'
'AES-GCM'
'AES-KW'

`subtle.importKey(format, keyData, algorithm, extractable, keyUsages)`

format: {string} Must be one of 'raw', 'pkcs8', 'spki', or 'jwk'.
keyData: {ArrayBuffer|TypedArray|DataView|Buffer|KeyObject}

algorithm: {AlgorithmIdentifier|RsaHashedImportParams|EcKeyImportParams|HmacImportParams}

extractable: {boolean}
keyUsages: {string[]} See Key usages.
Returns: {Promise} containing {CryptoKey}

The subtle.importKey() method attempts to interpret the provided keyData as the given format to create a {CryptoKey} instance using the provided algorithm, extractable, and keyUsages arguments. If the import is successful, the returned promise will be resolved with the created {CryptoKey}.

If importing a 'PBKDF2' key, extractable must be false.

The algorithms currently supported include:

Key Type	`'spki'`	`'pkcs8'`	`'jwk'`	`'raw'`
`'AES-CBC'`			✔	✔
`'AES-CTR'`			✔	✔
`'AES-GCM'`			✔	✔
`'AES-KW'`			✔	✔
`'ECDH'`	✔	✔	✔	✔
`'X25519'`[^1]	✔	✔	✔	✔
`'X448'`[^1]	✔	✔	✔	✔
`'ECDSA'`	✔	✔	✔	✔
`'Ed25519'`[^1]	✔	✔	✔	✔
`'Ed448'`[^1]	✔	✔	✔	✔
`'HDKF'`				✔
`'HMAC'`			✔	✔
`'PBKDF2'`				✔
`'RSA-OAEP'`	✔	✔	✔
`'RSA-PSS'`	✔	✔	✔
`'RSASSA-PKCS1-v1_5'`	✔	✔	✔

`subtle.sign(algorithm, key, data)`

algorithm: {AlgorithmIdentifier|RsaPssParams|EcdsaParams|Ed448Params}
key: {CryptoKey}
data: {ArrayBuffer|TypedArray|DataView|Buffer}
Returns: {Promise} containing {ArrayBuffer}

Using the method and parameters given by algorithm and the keying material provided by key, subtle.sign() attempts to generate a cryptographic signature of data. If successful, the returned promise is resolved with an {ArrayBuffer} containing the generated signature.

The algorithms currently supported include:

'RSASSA-PKCS1-v1_5'
'RSA-PSS'
'ECDSA'
'Ed25519'[^1]
'Ed448'[^1]
'HMAC'

`subtle.unwrapKey(format, wrappedKey, unwrappingKey, unwrapAlgo, unwrappedKeyAlgo, extractable, keyUsages)`

format: {string} Must be one of 'raw', 'pkcs8', 'spki', or 'jwk'.
wrappedKey: {ArrayBuffer|TypedArray|DataView|Buffer}
unwrappingKey: {CryptoKey}

unwrapAlgo: {AlgorithmIdentifier|RsaOaepParams|AesCtrParams|AesCbcParams|AesGcmParams}
unwrappedKeyAlgo: {AlgorithmIdentifier|RsaHashedImportParams|EcKeyImportParams|HmacImportParams}

extractable: {boolean}
keyUsages: {string[]} See Key usages.
Returns: {Promise} containing {CryptoKey}

In cryptography, “wrapping a key” refers to exporting and then encrypting the keying material. The subtle.unwrapKey() method attempts to decrypt a wrapped key and create a {CryptoKey} instance. It is equivalent to calling subtle.decrypt() first on the encrypted key data (using the wrappedKey, unwrapAlgo, and unwrappingKey arguments as input) then passing the results in to the subtle.importKey() method using the unwrappedKeyAlgo, extractable, and keyUsages arguments as inputs. If successful, the returned promise is resolved with a {CryptoKey} object.

The wrapping algorithms currently supported include:

'RSA-OAEP'
'AES-CTR'
'AES-CBC'
'AES-GCM'
'AES-KW'

The unwrapped key algorithms supported include:

'RSASSA-PKCS1-v1_5'
'RSA-PSS'
'RSA-OAEP'
'ECDSA'
'ECDH'
'HMAC'
'AES-CTR'
'AES-CBC'
'AES-GCM'
'AES-KW'

`subtle.verify(algorithm, key, signature, data)`

algorithm: {AlgorithmIdentifier|RsaPssParams|EcdsaParams|Ed448Params}
key: {CryptoKey}
signature: {ArrayBuffer|TypedArray|DataView|Buffer}
data: {ArrayBuffer|TypedArray|DataView|Buffer}
Returns: {Promise} containing {boolean}

Using the method and parameters given in algorithm and the keying material provided by key, subtle.verify() attempts to verify that signature is a valid cryptographic signature of data. The returned promise is resolved with either true or false.

The algorithms currently supported include:

'RSASSA-PKCS1-v1_5'
'RSA-PSS'
'ECDSA'
'Ed25519'[^1]
'Ed448'[^1]
'HMAC'

`subtle.wrapKey(format, key, wrappingKey, wrapAlgo)`

format: {string} Must be one of 'raw', 'pkcs8', 'spki', or 'jwk'.
key: {CryptoKey}
wrappingKey: {CryptoKey}
wrapAlgo: {AlgorithmIdentifier|RsaOaepParams|AesCtrParams|AesCbcParams|AesGcmParams}
Returns: {Promise} containing {ArrayBuffer}

In cryptography, “wrapping a key” refers to exporting and then encrypting the keying material. The subtle.wrapKey() method exports the keying material into the format identified by format, then encrypts it using the method and parameters specified by wrapAlgo and the keying material provided by wrappingKey. It is the equivalent to calling subtle.exportKey() using format and key as the arguments, then passing the result to the subtle.encrypt() method using wrappingKey and wrapAlgo as inputs. If successful, the returned promise will be resolved with an {ArrayBuffer} containing the encrypted key data.

The wrapping algorithms currently supported include:

'RSA-OAEP'
'AES-CTR'
'AES-CBC'
'AES-GCM'
'AES-KW'

Algorithm parameters

The algorithm parameter objects define the methods and parameters used by the various {SubtleCrypto} methods. While described here as “classes”, they are simple JavaScript dictionary objects.

Class: `AlgorithmIdentifier`

`algorithmIdentifier.name`

Type: {string}

Class: `AesCbcParams`

`aesCbcParams.iv`

Type: {ArrayBuffer|TypedArray|DataView|Buffer}

Provides the initialization vector. It must be exactly 16-bytes in length and should be unpredictable and cryptographically random.

`aesCbcParams.name`

Type: {string} Must be 'AES-CBC'.

Class: `AesCtrParams`

`aesCtrParams.counter`

Type: {ArrayBuffer|TypedArray|DataView|Buffer}

The initial value of the counter block. This must be exactly 16 bytes long.

The AES-CTR method uses the rightmost length bits of the block as the counter and the remaining bits as the nonce.

`aesCtrParams.length`

Type: {number} The number of bits in the aesCtrParams.counter that are to be used as the counter.

`aesCtrParams.name`

Type: {string} Must be 'AES-CTR'.

Class: `AesGcmParams`

`aesGcmParams.additionalData`

Type: {ArrayBuffer|TypedArray|DataView|Buffer|undefined}

With the AES-GCM method, the additionalData is extra input that is not encrypted but is included in the authentication of the data. The use of additionalData is optional.

`aesGcmParams.iv`

Type: {ArrayBuffer|TypedArray|DataView|Buffer}

The initialization vector must be unique for every encryption operation using a given key.

Ideally, this is a deterministic 12-byte value that is computed in such a way that it is guaranteed to be unique across all invocations that use the same key. Alternatively, the initialization vector may consist of at least 12 cryptographically random bytes. For more information on constructing initialization vectors for AES-GCM, refer to Section 8 of NIST SP 800-38D.

`aesGcmParams.name`

Type: {string} Must be 'AES-GCM'.

`aesGcmParams.tagLength`

Type: {number} The size in bits of the generated authentication tag. This values must be one of 32, 64, 96, 104, 112, 120, or 128. Default: 128.

Class: `AesKeyGenParams`

`aesKeyGenParams.length`

Type: {number}

The length of the AES key to be generated. This must be either 128, 192, or 256.

`aesKeyGenParams.name`

Type: {string} Must be one of 'AES-CBC', 'AES-CTR', 'AES-GCM', or 'AES-KW'

Class: `EcdhKeyDeriveParams`

`ecdhKeyDeriveParams.name`

Type: {string} Must be 'ECDH', 'X25519', or 'X448'.

`ecdhKeyDeriveParams.public`

Type: {CryptoKey}

ECDH key derivation operates by taking as input one parties private key and another parties public key -- using both to generate a common shared secret. The ecdhKeyDeriveParams.public property is set to the other parties public key.

Class: `EcdsaParams`

`ecdsaParams.hash`

Type: {string|Object}

If represented as a {string}, the value must be one of:

'SHA-1'
'SHA-256'
'SHA-384'
'SHA-512'

If represented as an {Object}, the object must have a name property whose value is one of the above listed values.

`ecdsaParams.name`

Type: {string} Must be 'ECDSA'.

Class: `EcKeyGenParams`

`ecKeyGenParams.name`

Type: {string} Must be one of 'ECDSA' or 'ECDH'.

`ecKeyGenParams.namedCurve`

Type: {string} Must be one of 'P-256', 'P-384', 'P-521'.

Class: `EcKeyImportParams`

`ecKeyImportParams.name`

Type: {string} Must be one of 'ECDSA' or 'ECDH'.

`ecKeyImportParams.namedCurve`

Type: {string} Must be one of 'P-256', 'P-384', 'P-521'.

Class: `Ed448Params`

`ed448Params.name`

Type: {string} Must be 'Ed448'.

`ed448Params.context`

Type: {ArrayBuffer|TypedArray|DataView|Buffer|undefined}

The context member represents the optional context data to associate with the message. The Node.js Web Crypto API implementation only supports zero-length context which is equivalent to not providing context at all.

Class: `HkdfParams`

`hkdfParams.hash`

Type: {string|Object}

If represented as a {string}, the value must be one of:

'SHA-1'
'SHA-256'
'SHA-384'
'SHA-512'

If represented as an {Object}, the object must have a name property whose value is one of the above listed values.

`hkdfParams.info`

Type: {ArrayBuffer|TypedArray|DataView|Buffer}

Provides application-specific contextual input to the HKDF algorithm. This can be zero-length but must be provided.

`hkdfParams.name`

Type: {string} Must be 'HKDF'.

`hkdfParams.salt`

Type: {ArrayBuffer|TypedArray|DataView|Buffer}

The salt value significantly improves the strength of the HKDF algorithm. It should be random or pseudorandom and should be the same length as the output of the digest function (for instance, if using 'SHA-256' as the digest, the salt should be 256-bits of random data).

Class: `HmacImportParams`

`hmacImportParams.hash`

Type: {string|Object}

If represented as a {string}, the value must be one of:

'SHA-1'
'SHA-256'
'SHA-384'
'SHA-512'

If represented as an {Object}, the object must have a name property whose value is one of the above listed values.

`hmacImportParams.length`

Type: {number}

The optional number of bits in the HMAC key. This is optional and should be omitted for most cases.

`hmacImportParams.name`

Type: {string} Must be 'HMAC'.

Class: `HmacKeyGenParams`

`hmacKeyGenParams.hash`

Type: {string|Object}

If represented as a {string}, the value must be one of:

'SHA-1'
'SHA-256'
'SHA-384'
'SHA-512'

If represented as an {Object}, the object must have a name property whose value is one of the above listed values.

`hmacKeyGenParams.length`

Type: {number}

The number of bits to generate for the HMAC key. If omitted, the length will be determined by the hash algorithm used. This is optional and should be omitted for most cases.

`hmacKeyGenParams.name`

Type: {string} Must be 'HMAC'.

Class: `Pbkdf2Params`

`pbkdb2Params.hash`

Type: {string|Object}

If represented as a {string}, the value must be one of:

'SHA-1'
'SHA-256'
'SHA-384'
'SHA-512'

If represented as an {Object}, the object must have a name property whose value is one of the above listed values.

`pbkdf2Params.iterations`

Type: {number}

The number of iterations the PBKDF2 algorithm should make when deriving bits.

`pbkdf2Params.name`

Type: {string} Must be 'PBKDF2'.

`pbkdf2Params.salt`

Type: {ArrayBuffer|TypedArray|DataView|Buffer}

Should be at least 16 random or pseudorandom bytes.

Class: `RsaHashedImportParams`

`rsaHashedImportParams.hash`

Type: {string|Object}

If represented as a {string}, the value must be one of:

'SHA-1'
'SHA-256'
'SHA-384'
'SHA-512'

If represented as an {Object}, the object must have a name property whose value is one of the above listed values.

`rsaHashedImportParams.name`

Type: {string} Must be one of 'RSASSA-PKCS1-v1_5', 'RSA-PSS', or 'RSA-OAEP'.

Class: `RsaHashedKeyGenParams`

`rsaHashedKeyGenParams.hash`

Type: {string|Object}

If represented as a {string}, the value must be one of:

'SHA-1'
'SHA-256'
'SHA-384'
'SHA-512'

If represented as an {Object}, the object must have a name property whose value is one of the above listed values.

`rsaHashedKeyGenParams.modulusLength`

Type: {number}

The length in bits of the RSA modulus. As a best practice, this should be at least 2048.

`rsaHashedKeyGenParams.name`

Type: {string} Must be one of 'RSASSA-PKCS1-v1_5', 'RSA-PSS', or 'RSA-OAEP'.

`rsaHashedKeyGenParams.publicExponent`

Type: {Uint8Array}

The RSA public exponent. This must be a {Uint8Array} containing a big-endian, unsigned integer that must fit within 32-bits. The {Uint8Array} may contain an arbitrary number of leading zero-bits. The value must be a prime number. Unless there is reason to use a different value, use new Uint8Array([1, 0, 1]) (65537) as the public exponent.

Class: `RsaOaepParams`

rsaOaepParams.label

Type: {ArrayBuffer|TypedArray|DataView|Buffer}

An additional collection of bytes that will not be encrypted, but will be bound to the generated ciphertext.

The rsaOaepParams.label parameter is optional.

rsaOaepParams.name

Type: {string} must be 'RSA-OAEP'.

Class: `RsaPssParams`

`rsaPssParams.name`

Type: {string} Must be 'RSA-PSS'.

`rsaPssParams.saltLength`

Type: {number}

The length (in bytes) of the random salt to use.

[^1]: An experimental implementation of Secure Curves in the Web Cryptography API as of 05 May 2022

Web Crypto API

Examples

Generating keys

AES keys

ECDSA key pairs

Ed25519/Ed448/X25519/X448 key pairs

HMAC keys

RSA key pairs

Encryption and decryption

Exporting and importing keys

Wrapping and unwrapping keys

Sign and verify

Deriving bits and keys

Digest

Algorithm matrix

Class: Crypto

crypto.subtle

crypto.getRandomValues(typedArray)

crypto.randomUUID()

Class: CryptoKey

cryptoKey.algorithm

cryptoKey.extractable

cryptoKey.type

cryptoKey.usages

Class: CryptoKeyPair

cryptoKeyPair.privateKey

cryptoKeyPair.publicKey

Class: SubtleCrypto

subtle.decrypt(algorithm, key, data)

subtle.deriveBits(algorithm, baseKey, length)

subtle.deriveKey(algorithm, baseKey, derivedKeyAlgorithm, extractable, keyUsages)

subtle.digest(algorithm, data)

subtle.encrypt(algorithm, key, data)

subtle.exportKey(format, key)

subtle.generateKey(algorithm, extractable, keyUsages)

subtle.importKey(format, keyData, algorithm, extractable, keyUsages)

subtle.sign(algorithm, key, data)

subtle.unwrapKey(format, wrappedKey, unwrappingKey, unwrapAlgo, unwrappedKeyAlgo, extractable, keyUsages)

subtle.verify(algorithm, key, signature, data)

subtle.wrapKey(format, key, wrappingKey, wrapAlgo)

Algorithm parameters

Class: AlgorithmIdentifier

algorithmIdentifier.name

Class: AesCbcParams

aesCbcParams.iv

aesCbcParams.name

Class: AesCtrParams

aesCtrParams.counter

aesCtrParams.length

aesCtrParams.name

Class: AesGcmParams

aesGcmParams.additionalData

aesGcmParams.iv

aesGcmParams.name

aesGcmParams.tagLength

Class: AesKeyGenParams

aesKeyGenParams.length

aesKeyGenParams.name

Class: EcdhKeyDeriveParams

ecdhKeyDeriveParams.name

ecdhKeyDeriveParams.public

Class: EcdsaParams

ecdsaParams.hash

ecdsaParams.name

Class: EcKeyGenParams

ecKeyGenParams.name

ecKeyGenParams.namedCurve

Class: EcKeyImportParams

ecKeyImportParams.name

ecKeyImportParams.namedCurve

Class: Ed448Params

ed448Params.name

ed448Params.context

Class: HkdfParams

hkdfParams.hash

hkdfParams.info

hkdfParams.name

hkdfParams.salt

Class: HmacImportParams

hmacImportParams.hash

Class: `Crypto`

`crypto.subtle`

`crypto.getRandomValues(typedArray)`

`crypto.randomUUID()`

Class: `CryptoKey`

`cryptoKey.algorithm`

`cryptoKey.extractable`

`cryptoKey.type`

`cryptoKey.usages`

Class: `CryptoKeyPair`

`cryptoKeyPair.privateKey`

`cryptoKeyPair.publicKey`

Class: `SubtleCrypto`

`subtle.decrypt(algorithm, key, data)`

`subtle.deriveBits(algorithm, baseKey, length)`

`subtle.deriveKey(algorithm, baseKey, derivedKeyAlgorithm, extractable, keyUsages)`

`subtle.digest(algorithm, data)`

`subtle.encrypt(algorithm, key, data)`

`subtle.exportKey(format, key)`

`subtle.generateKey(algorithm, extractable, keyUsages)`

`subtle.importKey(format, keyData, algorithm, extractable, keyUsages)`

`subtle.sign(algorithm, key, data)`

`subtle.unwrapKey(format, wrappedKey, unwrappingKey, unwrapAlgo, unwrappedKeyAlgo, extractable, keyUsages)`

`subtle.verify(algorithm, key, signature, data)`

`subtle.wrapKey(format, key, wrappingKey, wrapAlgo)`

Class: `AlgorithmIdentifier`

`algorithmIdentifier.name`

Class: `AesCbcParams`

`aesCbcParams.iv`

`aesCbcParams.name`

Class: `AesCtrParams`

`aesCtrParams.counter`

`aesCtrParams.length`

`aesCtrParams.name`

Class: `AesGcmParams`

`aesGcmParams.additionalData`

`aesGcmParams.iv`

`aesGcmParams.name`

`aesGcmParams.tagLength`

Class: `AesKeyGenParams`

`aesKeyGenParams.length`

`aesKeyGenParams.name`

Class: `EcdhKeyDeriveParams`

`ecdhKeyDeriveParams.name`

`ecdhKeyDeriveParams.public`

Class: `EcdsaParams`

`ecdsaParams.hash`

`ecdsaParams.name`

Class: `EcKeyGenParams`

`ecKeyGenParams.name`

`ecKeyGenParams.namedCurve`

Class: `EcKeyImportParams`

`ecKeyImportParams.name`

`ecKeyImportParams.namedCurve`

Class: `Ed448Params`

`ed448Params.name`

`ed448Params.context`

Class: `HkdfParams`

`hkdfParams.hash`

`hkdfParams.info`

`hkdfParams.name`

`hkdfParams.salt`

Class: `HmacImportParams`

`hmacImportParams.hash`

`hmacImportParams.length`

`hmacImportParams.name`

Class: `HmacKeyGenParams`

`hmacKeyGenParams.hash`

`hmacKeyGenParams.length`

`hmacKeyGenParams.name`

Class: `Pbkdf2Params`

`pbkdb2Params.hash`

`pbkdf2Params.iterations`

`pbkdf2Params.name`

`pbkdf2Params.salt`

Class: `RsaHashedImportParams`

`rsaHashedImportParams.hash`

`rsaHashedImportParams.name`

Class: `RsaHashedKeyGenParams`

`rsaHashedKeyGenParams.hash`