<!--
{
  "availability" : [
    "iOS: 17.0.0 -",
    "iPadOS: 17.0.0 -",
    "macCatalyst: 17.0.0 -",
    "macOS: 14.0.0 -",
    "tvOS: 17.0.0 -",
    "visionOS: 1.0.0 -",
    "watchOS: 10.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "CryptoKit",
  "identifier" : "/documentation/CryptoKit/KEM",
  "metadataVersion" : "0.1.0",
  "role" : "Enumeration",
  "symbol" : {
    "kind" : "Enumeration",
    "modules" : [
      "Apple CryptoKit"
    ],
    "preciseIdentifier" : "s:9CryptoKit3KEMO"
  },
  "title" : "KEM"
}
-->

# KEM

A key encapsulation mechanism.

```
enum KEM
```

## Overview

Use a key encapsulation mechanism (KEM) to protect a symmetric cryptographic key that you share with another party.

## Topics

### Defining encapsulation outputs

[`struct EncapsulationResult`](/documentation/CryptoKit/KEM/EncapsulationResult)

The result of a key encapsulation operation.

### Handling errors

[`enum Errors`](/documentation/CryptoKit/KEM/Errors)

Errors that CryptoKit throws when it encounters problems in key encapsulation mechanism (KEM) operations.

## Relationships

### Conforms To

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Sendable`](/documentation/Swift/Sendable)

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)