---
title: "generateKey | Grafana k6 documentation"
description: "generateKey generates a new key."
---

> For a curated documentation index, see [llms.txt](/llms.txt). For the complete documentation index, see [llms-full.txt](/llms-full.txt).

# generateKey

The `generateKey()` generates a new cryptographic key and returns it as a [CryptoKey](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/cryptokey/) object or a [CryptoKeyPair](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/cryptokeypair/) object that can be used with the Web Crypto API.

## Usage

![Copy code to clipboard](https://grafana.com/media/images/icons/icon-copy-small-2.svg) Copy

```none
generateKey(algorithm, extractable, keyUsages)
```

## Parameters

Expand table

| Name          | Type                                                       | Description                                                                                                                                                      |
|---------------|------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `algorithm`   | a `string` or algorithm object with a single `name` string | The type of key to generate. It can be either a string with any of the currently supported algorithms as a value or any of the generation key parameter objects. |
| `extractable` | `boolean`                                                  | Whether the key can be exported using [exportKey](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/subtlecrypto/exportkey/).                             |
| `keyUsages`   | `Array<string>`                                            | An array of strings describing what operations can be performed with the key. Key usages could vary depending on the algorithm.                                  |

### Supported algorithms

Expand table

| AES-CBC                                                                                  | AES-CTR                                                                                  | AES-GCM                                                                                  | AES-KW | ECDH                                                                                                   | ECDSA                                                                                  | HMAC                                                                                             | PBKDF2                                                                                   | RSA-OAEP                                                                                                   | RSASSA-PKCS1-v1\_5                                                                                         | RSA-PSS                                                                                                    |
|------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------|--------|--------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------|
| ✅ [AesCbcParams](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/aescbcparams/) | ✅ [AesCtrParams](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/aesctrparams/) | ✅ [AesGcmParams](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/aesgcmparams/) | ❌      | ✅ [EcdhKeyDeriveParams](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/ecdhkeyderiveparams/) | ✅ [EcdsaParams](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/ecdsaparams/) | ✅ [HmacKeyGenParams](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/hmackeygenparams/) | ✅ [Pbkdf2Params](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/pbkdf2params/) | ✅ [RsaHashedImportParams](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/rsahashedimportparams/) | ✅ [RsaHashedImportParams](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/rsahashedimportparams/) | ✅ [RsaHashedImportParams](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/rsahashedimportparams/) |

## Return Value

A `Promise` that resolves with the generated key as a [CryptoKey](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/cryptokey/) object or a [CryptoKeyPair](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/cryptokeypair/) object.

### Algorithm specific input

Expand table

|                        | HMAC                                                                                             | AES                                                                                            | ECDH                                                                                         | ECDSA                                                                                        | RSA-OAEP                                                                                                   | RSASSA-PKCS1-v1\_5                                                                                         | RSA-PSS                                                                                                    |
|------------------------|--------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------|
| Parameters type to use | [`HmacKeyGenParams`](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/hmackeygenparams/) | [`AesKeyGenParams`](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/aeskeygenparams/) | [`EcKeyGenParams`](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/eckeygenparams/) | [`EcKeyGenParams`](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/eckeygenparams/) | [`RSAHashedKeyGenParams`](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/rsahashedkeygenparams/) | [`RSAHashedKeyGenParams`](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/rsahashedkeygenparams/) | [`RSAHashedKeyGenParams`](https://grafana.com/docs/k6/v2.3.x/javascript-api/crypto/rsahashedkeygenparams/) |
| Possible key usages    | `sign`, `verify`                                                                                 | `encrypt`, `decrypt`                                                                           | `deriveKey`, `deriveBits`                                                                    | `sign`, `verify`                                                                             | `encrypt`, `decrypt`                                                                                       | `sign`, `verify`                                                                                           | `sign`, `verify`                                                                                           |

## Throws

Expand table

| Type          | Description                                                                                   |
|---------------|-----------------------------------------------------------------------------------------------|
| `SyntaxError` | Raised when the `keyUsages` parameter is empty, but the key is of type `secret` or `private`. |

## Example

JavaScript ![Copy code to clipboard](https://grafana.com/media/images/icons/icon-copy-small-2.svg) Copy

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

  console.log(JSON.stringify(key));
}
```