---
title: samplingFrequency
framework: healthkit
role: symbol
role_heading: Instance Property
path: healthkit/hkelectrocardiogram/samplingfrequency
---

# samplingFrequency

The frequency at which the Apple Watch sampled the voltage.

## Declaration

```swift
@NSCopying var samplingFrequency: HKQuantity? { get }
```

## Discussion

Discussion The system records the frequency in hertz() units.

## See Also

### Accessing Voltage Measurements

- [numberOfVoltageMeasurements](healthkit/hkelectrocardiogram/numberofvoltagemeasurements.md)
- [HKElectrocardiogram.VoltageMeasurement](healthkit/hkelectrocardiogram/voltagemeasurement.md)
- [HKElectrocardiogram.Lead](healthkit/hkelectrocardiogram/lead.md)