# ivLengthForAlg

> **ivLengthForAlg**(`alg`): `number`

Defined in: [packages/filecoin-encryption-envelope/src/cose/headers.ts:323](https://github.com/FilOzone/synapse-sdk/blob/9ad84d812e1dd635b76420a7d9388555a04f31b6/packages/filecoin-encryption-envelope/src/cose/headers.ts#L323)

The IV length this profile requires for `alg`: 12 bytes (scheme 1) or 7 bytes (chunked base nonce).

## Parameters

| Parameter | Type |
| ------ | ------ |
| `alg` | [`Alg`](/reference/filoz/filecoin-encryption-envelope/namespaces/cose/type-aliases/alg/) |

## Returns

`number`