---
title: kSpeechRateProperty
framework: applicationservices
role: symbol
role_heading: Global Variable
path: applicationservices/kspeechrateproperty
---

# kSpeechRateProperty

Get or set a speech channel’s speech rate.

## Declaration

```swift
let kSpeechRateProperty: CFString
```

## Discussion

Discussion The value associated with this property is a CFNumber object that specifies the speech channel’s speaking rate.  The range of supported rates is not predefined by the Speech Synthesis Manager; each speech synthesizer provides its own range of speech rates. Average human speech occurs at a rate of 180 to 220 words per minute. This property works with the CopySpeechProperty(_:_:_:) and SetSpeechProperty(_:_:_:) functions.