Apple Watch Series 12 Heart Rate Study: Ranking All Wearables!

Name: Apple Watch Series 12 Heart Rate Study: Ranking All Wearables!
Uploaded: 2026-09-10T01:01:41.000Z
Duration: 8 min 47 s
Channel: The Quantified Scientist

The Quantified ScientistSeptember 10, 20268m

Topics16

Apple Watch Series 12 Heart Rate Accuracy Claims0:00 Study Design and Participant Details0:31 Testing Methodology and Competitor Comparison1:30 Exercise Testing Protocol2:01 Background Heart Rate and Measurement Metrics2:32 Data Visualization and Comparison Method3:01 Exercise-Specific Results Analysis3:30 Smart Watch vs Sport Company Performance4:31 Strength Training and Dropout Rate Concerns5:00 Overall Device Rankings5:31 Daily Living Measurements6:01 Performance Consistency Analysis6:32 Study Limitations and Methodological Questions7:01 Study Independence and Validation Efforts7:31 Technical Measurement Concerns8:01 Independent Verification Recommendations8:30

In a Nutshell

Apple's head-to-head study of 1,254 people found the Series 12 the most accurate optical heart-rate wearable, with the Pixel Watch 4 a close second and Huawei Watch 5 third across running, cycling, HIIT, strength work, and daily living; Garmin, Whoop, Galaxy Watch, and Oura Ring trailed. The ranking held whether Apple used mean absolute error or RMSE versus a Polar H10 ECG chest strap. Key caveats remain: dropout handling wasn’t disclosed, and the study was Apple-run, so independent verification is still needed.

AI-Generated Notes

These notes were generated by AI and may contain inaccuracies.

Apple claims that the new Apple Watch Series 12 and Ultra 4 have the most accurate heart rate sensing of any wearable from any brand. The study results show which competitors Apple considers best and worst, and the analysis examines what the results do and do not demonstrate.

The study enrolled 1460 participants with 1254 contributing data to the final analysis, representing just over 1200 people. Participants wore both an Apple Watch Series 12 on one wrist and a competing wearable on the other wrist. The Polar H10 ECG chest strap served as the reference device. The Apple Watch and competitor were randomly placed on left and right wrists, meaning the Apple Watch was approximately 50% of the time on the dominant hand and 50% on the non-dominant hand.

The testing setup is fundamentally similar to independent testing methods that compare wearables directly against an ECG chest strap, specifically the same Polar H10 model. Apple compared the Series 12 against the Garmin Forerunner 970, the Pixel Watch 4, the Huawei Watch 5, the Galaxy Watch 8, the Whoop Strap 5.0, and the Oura Ring 5.

Participants completed outdoor running, treadmill interval cycling, HIIT exercises, and strength training. These conditions were selected because they include many scenarios that challenge optical heart rate sensors, including cadence lock during running, gripping during cycling and weightlifting, and rapid heart rate changes during intervals.

Background heart rate measurements were tested during rest, desk work, meal prep, and walking. Apple primarily evaluated accuracy using mean absolute error and root mean square error (RMSE). Mean absolute error calculates how far each watch measurement is from the ECG reference, ignores whether measurements were too high or too low, and averages that error. RMSE is similar but gives more weight to larger errors. Results are essentially the same regardless of which metric is used, so RMSE is emphasized as it is the first metric shown.

Apple does not plot the absolute accuracy of the Apple Watch and competing devices. Instead, they subtract the two values from each other. Values left of zero indicate the Apple Watch performed better, while values right of zero indicate the competing device performed better.

For outdoor cycling, the average results across all participants showed the Apple Watch performing better than all devices except for the Pixel Watch 4, where there was no significant difference. In running tests, the second best device after the Apple Watch was the Pixel Watch 4, followed by the Huawei Watch 5, then the Garmin 970. For indoor running, the ranking was again Pixel Watch 4 as second best, followed by Huawei Watch 5, then the Whoop Strap.

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Apple Watch Series 12 Heart Rate Study: Ranking All Wearables!

Apple Watch Series 12 Heart Rate Accuracy Claims00:00

Study Design and Participant Details00:31

Testing Methodology and Competitor Comparison01:30

Exercise Testing Protocol02:01

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