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# SecKeySizes

The supported sizes for keys of various common types.

```
enum SecKeySizes
```

## Topics

### Constants

[`SecKeySizes.secDefaultKeySize`](/documentation/Security/SecKeySizes/secDefaultKeySize)

The default key size for the specified type.

[`SecKeySizes.sec3DES192`](/documentation/Security/SecKeySizes/sec3DES192)

192-bit DES.

[`SecKeySizes.secAES128`](/documentation/Security/SecKeySizes/secAES128)

128-bit AES.

[`secAES192`](/documentation/Security/SecKeySizes/secAES192)

192-bit AES.

[`SecKeySizes.secAES256`](/documentation/Security/SecKeySizes/secAES256)

256-bit AES.

[`secp192r1`](/documentation/Security/SecKeySizes/secp192r1)

192-bit ECC Keys for Suite-B from RFC 4492 section 5.1.1.

[`secp256r1`](/documentation/Security/SecKeySizes/secp256r1)

256-bit ECC Keys for Suite-B from RFC 4492 section 5.1.1.

[`SecKeySizes.secp384r1`](/documentation/Security/SecKeySizes/secp384r1)

384-bit ECC Keys for Suite-B from RFC 4492 section 5.1.1.

[`SecKeySizes.secp521r1`](/documentation/Security/SecKeySizes/secp521r1)

521-bit ECC Keys for Suite-B from RFC 4492 section 5.1.1.

[`SecKeySizes.secRSAMin`](/documentation/Security/SecKeySizes/secRSAMin)

1024 bits is the minimum size for an RSA key.

[`SecKeySizes.secRSAMax`](/documentation/Security/SecKeySizes/secRSAMax)

4096 bits is the maximum size for an RSA key.


---

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