Just how accurate is the Apple Watch heart rate monitor? Surprisingly accurate. In fact, it's pretty much in line with the Mio Alpha, which is considered to be as accurate as traditional chest strap heart rate monitors.
Apple Watch and Mio Alpha heart rate monitor comparison
SonoPlot founder Brad Larson pitted the two against each other, and what he found is that the results were nearly identical. He shared his results in a graph posted to his Twitter account.
Mio Alpha is a wrist-word dedicated heart rate monitor known for its high accuracy comparison to chest strap-style monitors. Mia Alpha's accuracy is high enough and consistent enough it's the go-to choice for many athletes and physical fitness enthusiasts.
Apple Watch, which is Apple's new smartwatch and fitness tracker, includes a heart rate sensor as well. Until now, however, we haven't had quantifiable data showing just how accurate it is.
Apple Watch heart rate sensors
The slight differences in readings between the two devices might simply be a side effect of how often they snap heart rate readings. The Mio Alpha captures data every three seconds, where Apple Watch gathers its readings at five second intervals. Since that capture rate is software-based, Apple could potentially increase heart rate monitoring accuracy with an update that shortens the reading cycle.
Still, Apple Watch's heart rate readings are surprisingly accurate, which is great news especially considering the device is so much more than a fitness tracker.