How to view your HRV history on iPhone
Apple Watch writes heart rate variability to the Health app, which shows it as a single-metric chart. Health Stats reads the same HRV data and charts it by Day, Week, Month and Year, lets you swipe back through earlier periods, overlays the previous period for comparison, shows the lowest, median and highest for the range, lists record values with dates, and names the device that recorded each reading. HRV is a Pro metric; the app is read-only and works offline.
What HRV is in Health, and what this page will not tell you
Apple Watch records heart rate variability as SDNN in milliseconds, mostly during rest and sleep, and stores it in Health under Heart Rate Variability. Health Stats displays those values. It does not rate them: what counts as a good or bad HRV depends on the person, and this app and this page make no claim about it. If you have a health concern, that is a question for a clinician, not a chart.
Reading the trend instead of single days
Day-to-day HRV jumps around, which is why the single-number view in Health is hard to use. In Health Stats the Month and Year views show the shape, the Compare overlay puts last month or last year underneath, and the distribution bar summarises the range as lowest, median and highest. Insights flag the highest and lowest recorded values and the dates. For the month-over-month mechanics see comparing Apple Health periods.
Every HRV reading in order
The Timeline tab lists each HRV sample with its time, so you can see when the Watch actually measured (typically overnight and during still periods) and which device wrote it. That is also where duplicates from a second wearable would show up.
What this cannot do
- HRV is a Pro metric; the free tier is steps, walking + running distance and active energy.
- The app charts values; it does not interpret HRV, set targets or give health or training advice.
- It cannot record HRV itself and has no Watch app; it depends on what Health already holds.
- iPhone only, iOS 15 or later.
Questions people ask
Why does my HRV history have gaps?
The Watch measures HRV opportunistically, mostly at rest, so days with little still time can have no sample. Health Stats shows gaps as gaps — its heat map and Insights call out days with no data rather than filling them in.
Health Stats: Data & Charts
Charts, trends and records for 97 Apple Health metrics. Read-only, offline.