---
title: kMDItemKeySignature
framework: coreservices
role: symbol
role_heading: Global Variable
path: coreservices/kmditemkeysignature
---

# kMDItemKeySignature

The key of the music contained in the audio file. For example: C, Dm, F#m, Bb. A CFString.

## Declaration

```swift
let kMDItemKeySignature: CFString!
```