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# estimatedScaleFactor

A factor that relates the body’s default height with the height ARKit estimates at runtime.

```
var estimatedScaleFactor: CGFloat { get }
```

## Discussion

The default value is 1.0. If you set [`automaticSkeletonScaleEstimationEnabled`](/documentation/ARKit/ARBodyTrackingConfiguration/automaticSkeletonScaleEstimationEnabled) to <doc://com.apple.documentation/documentation/Swift/true> on [`ARBodyTrackingConfiguration`](/documentation/ARKit/ARBodyTrackingConfiguration), ARKit sets this property to a value between 0.0 and 1.0.

ARKit must know the height of a person in the camera feed to estimate an accurate world position for the person’s body anchor. ARKit uses the value of [`estimatedScaleFactor`](/documentation/ARKit/ARBodyAnchor/estimatedScaleFactor) to correct the body anchor’s position in the physical environment.

The default body is 1.8 meters tall.

---

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