Changes to heart rate chart and low heart rate warnings on Apple Watch Series 12

That makes sense. The Series 12 samples the background heart rate every 5 seconds, all day long. Series 11 and older models sampled heart rate in the background roughly every 5 minutes (or sporadically, depending on movement and activity state). 

I know I have mild PVC's, but now it shows every reading as a range like 75-80 instead of just 75 like on my prior watch. I still have that watch and it records the single reading when I wear it, so it's something with the new update on the Series 12 heart readings that show every reading as a range of heartbeats.

You did a great job describing it.

Sorry, I've got more questions. Do you mean the heart rate information in Health? Or do you mean the notifications you get. The notifications, according to Apple, should look like the picture in this support article.

https://support.apple.com/en-us/120276

I keep trying to post a screenshot from my Health app but the forums are wonky today. Of the three notificatioins I can see on the High Heart Rate Notifications page in Health, two are from October 2025 and one is from June 2025, well before watchOS 12. They all show a range:

Oct 21, 2025 1:46PM 120-125 BPM

Oct 21, 2025 1:16PM 119-126 BPM

Jun 4, 2025 9:07AM 118-128 BPM

I've got data going back to 2017 and it's always a range.

It’s in the daily readings. The left side shows my Series 10 watch and the right side shows Series 12

[Edited by Moderator]

cynthiafromtucson wrote:

I've noticed a big change in the heart rate monitor on the Series 12 watch. Has anyone noticed the change in how their heart rate chart is showing the heart rate and low heart rate warnings?

It might help if you described the changes you're seeing.

Thank you, just did. It's a little hard to describe, but I tried!