We may earn a commission from links on this page.

I now have the Apple Watch Series 12 in my hands—or, rather, on my wrist—and have spent the past 24 hours putting it through as many tests as I can manage. I'm pleased with the step counting and the availability of "recovery HRV" (as opposed to the cardiac-health-focused HRV that the Apple Watch previously used) but I'm not sure if the heart rate accuracy is living up to the hype. I'll be putting this device to more rigorous tests, but here are my first thoughts.

Apple Watch Series 12 $399.00 at Amazon Learn More Learn More $399.00 at Amazon Apple redesigned the heart rate sensor on the back of the watch. Left: Apple Watch Series 11. Right: Apple Watch Series 12 Credit: Beth Skwarecki Step counting is everything I hoped it would be

Apple waited forever to add step counting as an easily viewable metric on the watch, but it’s finally here. I can open my smart stack (with a double pinch of my fingers, not even touching the watch screen) and see my steps right on top. I’ve also added a step count complication to my watch face. You can find this complication under Activity. The option to see your rings as a complication is still there, but you can now also add steps or wheelchair pushes.

Step counts work well. They update quickly, and seem to be accurate in my casual counting—nine steps from my desk to the door registers as nine steps. I’ll do more in-depth testing soon, to properly evaluate Apple’s claim that it now has the most accurate step counting out there. 

What’s disappointing is that it took so long—and that step counting is not coming to the Series 11 or any earlier watch. Apple’s step counting uses a special pedometer model that’s built into its new processor. Older Apple watches don’t have the hardware to calculate your steps as precisely, leading Apple to leave the feature off those watches. That is wild to me, considering that every other wearable has had step counts on the watch ever since the first cave dweller strapped a rock to their wrist. 

I’m not sure I buy these “most accurate heart rate” claims

Apple claims the Series 12 has the most accurate heart rate in a wearable, and I’ve already mentioned that that's a bold claim given what I’ve seen in the past from Apple and from other devices. Now that I have a Series 12 in my hands, I was able to do some preliminary testing. 

To be totally clear, these are not thorough tests, and I’m not making a decisive conclusion based on just a few days’ testing. But I’ll show you what I’ve tried so far. 

As always, I’m testing the device against my heart rate as read by a chest strap (the gold standard for heart rate comparisons). I did: 

  • A treadmill interval run with the Series 11 and a chest strap

  • An identical treadmill interval run with the Series 12, a chest strap, and the Garmin Forerunner 570 for good measure

  • An outdoor run that included steady jogging, intervals, and walking, with the Series 12, a chest strap, and the 570. 

I’m including the 570 in these tests because it has what I would consider the most accurate heart rate sensor in a wearable. In my past testing it’s reported numbers that were identical or nearly identical to the chest strap. That said, there’s always variation from day to day, and it didn’t shine quite as well in these recent tests compared to some I’ve done in the past. 

Apple Watch Series 11, top, and 12, bottom. Red dots are the Apple Watches; gray is the chest strap for reference. Credit: Beth Skwarecki

Here are the indoor runs with the Series 11 on top, and the Series 12 on the bottom, both in red and both compared to a chest strap. The Series 11 was already doing a pretty good job, and to be honest I’m not sure if the Series 12 is any better. I’m disappointed that the Series 12 is still only sampling heart rate every five seconds during workouts. Other devices, like the chest strap and the Garmin, sample every second. That means Apple is taking 12 data points every minute while these other devices are taking 60. 

Apple Watch Series 12 in red, Garmin Forerunner 570 in blue, chest strap for reference in gray Credit: Beth Skwarecki

Here’s the outdoor run. The chest strap is in gray, Garmin in blue, and Apple in red. Again, the sparse data points of the Apple watch aren’t impressive. I see a few places where Apple missed the peak of a small spike, but then again the Garmin struggled in a few spots as well. I’ll do further testing and report back when I’ve been able to try out the watch in a greater variety of activities and conditions.

What I can’t test yet

Live Rewind and Siri Recaps aren’t available yet. Live Rewind is the feature where you can ask for a text transcription of whatever was said around you in the last 15 seconds. Recaps handle a longer timeframe—for example, to summarize a meeting. These features are coming later this year, and aren’t in the version of watchOS 27 that came with the watch. (I have not installed any beta software on the watch.) 

Readiness is another big feature coming soon, but I haven’t logged enough nights of sleep to get my scores yet—it needs about a week of data. As a preview, I am seeing my “recovery HRV” listed with my sleep data. Last night my HRV was 45 according to Apple, and 50 according to my Oura ring. HRV readings from different devices may vary, depending on exactly when they take their measurements, so I’ll be looking for trends rather than specific data points. If both devices agree on what is a high or a low reading for me, given my baseline, I’ll call that a success for Apple.