---
title: HKMetadataKeyTimeZone
framework: healthkit
role: symbol
role_heading: Global Variable
path: healthkit/hkmetadatakeytimezone
---

# HKMetadataKeyTimeZone

The user’s time zone when the HealthKit object was created.

## Declaration

```swift
let HKMetadataKeyTimeZone: String
```

## Discussion

Discussion This key takes a string value compatible with the NSTimeZone class’s timeZoneWithName: method. For best results when analyzing sleep samples, it’s recommended that you store time zone metadata with your sleep sample data.

## See Also

### General Keys

- [HKMetadataKeyExternalUUID](healthkit/hkmetadatakeyexternaluuid.md)
- [HKMetadataKeyWasUserEntered](healthkit/hkmetadatakeywasuserentered.md)
- [HKMetadataKeyQuantityClampedToLowerBound](healthkit/hkmetadatakeyquantityclampedtolowerbound.md)
- [HKMetadataKeyQuantityClampedToUpperBound](healthkit/hkmetadatakeyquantityclampedtoupperbound.md)