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# ExtractPrivateKeyFromPKCS8Bytes

# Function: extractPrivateKeyFromPKCS8Bytes()

> **extractPrivateKeyFromPKCS8Bytes**(`privateKey`): `Uint8Array`

Defined in: [crypto.ts:310](https://github.com/tkhq/sdk/blob/ee72856c3f450731d7501ab05001215768b71500/packages/crypto/src/crypto.ts#L310)

Accepts a private key Uint8Array in the PKCS8 format, and returns the encapsulated private key.

## Parameters

### privateKey

`Uint8Array`

A PKCS#8 private key structured with the key data at a specific position. The actual key starts at byte 36 and is 32 bytes long.

## Returns

`Uint8Array`

* The private key.