---
title: roll
framework: Vision
role: symbol
role_heading: Instance Property
platforms: [iOS 12.0+, iPadOS 12.0+, Mac Catalyst 13.1+, macOS 10.14+, tvOS 12.0+, visionOS 1.0+]
path: vision/vnfaceobservation/2980939-roll
---

# roll

The roll angle of a face in radians.

## Declaration

```swift
var roll: NSNumber? { get }
```

## Discussion

This value indicates the rotational angle of the face around the z-axis.

If the request doesn’t calculate the angle, the value is `nil`.

## See Also

### Determining Facial Orientation

- [yaw](yaw.md)
- [pitch](pitch.md)