---
title: uuid
framework: healthkit
role: symbol
role_heading: Instance Property
path: healthkit/hkworkoutactivity/uuid
---

# uuid

The activity’s universally unique identifier (UUID).

## Declaration

```swift
var uuid: UUID { get }
```

## Discussion

Discussion HealthKit assigns a UUID to the workout activity when you create it. If you want to add your own unique ID, add it to the activity’s metadata using the HKMetadataKeyExternalUUID key.

## See Also

### Accessing workout data

- [startDate](healthkit/hkworkoutactivity/startdate.md)
- [endDate](healthkit/hkworkoutactivity/enddate.md)
- [duration](healthkit/hkworkoutactivity/duration.md)
- [allStatistics](healthkit/hkworkoutactivity/allstatistics.md)
- [statistics(for:)](healthkit/hkworkoutactivity/statistics(for:).md)
- [metadata](healthkit/hkworkoutactivity/metadata.md)
- [workoutConfiguration](healthkit/hkworkoutactivity/workoutconfiguration.md)
- [workoutEvents](healthkit/hkworkoutactivity/workoutevents.md)