Automatic HRV Analysis

Hexoskin automatically calculates HRV values during rest or sleep activities only.

In fact, based on the literature, HRV values can only be accurately and meaningfully measured during a period with very minimal activity and movement. Movement can cause noise or outliers in the ECG signal and then bias the HRV calculation and interpretation.


There are 3 ways to calculate HRV using Hexoskin:

1) Rest Activity - this can be added as an “Activity” in the Hexoskin app during a recording session. Learn more about Tagging an Activity during a Recording Session on the App. Alternatively, you can add a period of “Rest” activity in a record on the dashboard after syncing your data. Learn more about Tagging an Activity within a Record.

Hexoskin automatically provides you with an RMSSD value after syncing the data. A minimum of 5 minutes is needed to calculate the HRV. 

2) 5 Minute Rest Test - this can be added as a “Fitness Test” in the Hexoskin app during a recording session. You will be asked to rest for 5 minutes and the RMSSD HRV value will be calculated after syncing the data. It is best to do this test while lying on your back.

3) Sleep Activity - Hexoskin algorithms will provide the following HRV values on the Dashboard after tagging a Sleep Activity and syncing the data: HRV HF (%), HRV HF Norm Min (%) and HRV HF Norm Max (%), as HF is the most commonly reported HRV metric for sleep in the literature. Hexoskin will also automatically detect a Sleep activity with a minimum of 4 hours of sleep. A minimum of 5 minutes of  Sleep is needed to calculate HRV from a Sleep Activity.

After syncing the Sleep data, these additional HRV parameters are provided in the “Statistics.csv” file when the data is exported from the Dashboard. 

  • HRV(HF) (%)
  • HRV HF Norm Min (%)
  • HRV HF Norm Max (%)
  • HRV LF Norm Avg (%)
  • HRV LF Avg (ms2)
  • HRV HF Avg (ms2)
  • RMSSD (ms)

Hexoskin also provides additional HRV metrics that can be accessed through an API request. To obtain an API* key, please contact 

* By using your developer keys, you agree to our API Terms and Conditions.


If you want to perform meaningful HRV analysis during wake or active periods, you need to upload your data in binary format and perform your analysis by eliminating outliers in the ECG signal. You can use the HxConvertSourceFile software to download multiple files at once for the same user.  

On the software, check the box "Use Tab '\t' delimiter (used by Kubios) [default is comma ',' delimiter]" when uploading files you want to use Kubios analysis software to do your HRV analysis.

You will then use the RR_interval files to perform your analysis (for more details refer to this link). If you need any help or assistance, please do not hesitate to contact our support team at