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# JWTGenerateSecret

Generates a cryptographically random HMAC secret and returns it Base64-encoded. Use this to create RFC 7518–compliant keys for HS256/384/512.

## Method Signature

```
JWTGenerateSecret( [bits] )
```

### Arguments

| Argument | Type      | Required | Description                                            | Default |
| -------- | --------- | -------- | ------------------------------------------------------ | ------- |
| `bits`   | `numeric` | No       | Key length in bits. Must be ≥ 128 and a multiple of 8. | `256`   |

### Returns

A Base64-encoded `string` of `bits / 8` random bytes.

## Examples

```javascript
secret256 = jwtGenerateSecret();       // 256-bit, suitable for HS256
secret384 = jwtGenerateSecret( 384 );  // 384-bit, suitable for HS384
secret512 = jwtGenerateSecret( 512 );  // 512-bit, suitable for HS512

// Save to an environment variable / secret manager
writeOutput( "JWT_HMAC_SECRET=" & secret256 );
```

## Related

* [JWTGenerateKeyPair()](/boxlang-framework/modularity/jwt/reference/built-in-functions/jwtgeneratekeypair.md) — asymmetric key pairs
* [Key Management Guide](/boxlang-framework/modularity/jwt/key-management.md)
* [Security Best Practices](/boxlang-framework/modularity/jwt/security-best-practices.md)


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