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# CMAbsoluteAltitudeData

Data that records a change in absolute altitude.

```
class CMAbsoluteAltitudeData
```

## Overview

Absolute altitude is only available on iPhone 12 and later and Apple Watch 6 or SE and later.

## Topics

### Accessing Altitude Data

[`var altitude: Double`](/documentation/CoreMotion/CMAbsoluteAltitudeData/altitude)

The absolute altitude of the device relative to sea level, measured in meters.

[`var accuracy: Double`](/documentation/CoreMotion/CMAbsoluteAltitudeData/accuracy)

The estimated uncertainty of the altimeter in meters, based on one standard deviation.

[`var precision: Double`](/documentation/CoreMotion/CMAbsoluteAltitudeData/precision)

The recommended resolution for the altitude, in meters.

## Relationships

### Conforms To

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Equatable`](/documentation/Swift/Equatable)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`CVarArg`](/documentation/Swift/CVarArg)

[`NSCopying`](/documentation/Foundation/NSCopying)

[`NSSecureCoding`](/documentation/Foundation/NSSecureCoding)

[`NSCoding`](/documentation/Foundation/NSCoding)

[`Hashable`](/documentation/Swift/Hashable)

### Inherits From

[`CMLogItem`](/documentation/CoreMotion/CMLogItem)

---

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