---
title: speed
framework: realitykit
role: symbol
role_heading: Instance Property
path: realitykit/animationdefinition/speed
---

# speed

A factor that increases or decreases the animation’s rate of playback.

## Declaration

```swift
var speed: Float { get set }
```

## Discussion

Discussion The default value is 1.0, which doesn’t alter the animation’s duration. A value of 2.0 indicates that the duration is half the normal rate. A value of 0.5 indicates that the duration is twice the normal rate. Negative values play the animation in reverse. This property doesn’t affect the animation’s delay.

## See Also

### Timing the animation

- [delay](realitykit/animationdefinition/delay.md)
- [duration](realitykit/animationdefinition/duration.md)
- [offset](realitykit/animationdefinition/offset.md)
- [trimDuration](realitykit/animationdefinition/trimduration.md)
- [trimStart](realitykit/animationdefinition/trimstart.md)
- [trimEnd](realitykit/animationdefinition/trimend.md)
- [trimmed(start:end:duration:)](realitykit/animationdefinition/trimmed(start:end:duration:).md)