---
title: heartRateVariabilityRMSSD
framework: HealthKit
role: symbol
role_heading: Type Property
platforms: [iOS 27.0+, iPadOS 27.0+, Mac Catalyst 27.0+, macOS 27.0+, visionOS 27.0+, watchOS 27.0+]
path: healthkit/hkquantitytypeidentifier/heartratevariabilityrmssd
---

# heartRateVariabilityRMSSD

## Declaration

```swift
static let heartRateVariabilityRMSSD: HKQuantityTypeIdentifier
```