Updated
Updated · 9to5Mac · Sep 11
Apple Study Says Watch Series 12 Beat Rivals in 139 of 159 Heart-Rate Tests
Updated
Updated · 9to5Mac · Sep 11

Apple Study Says Watch Series 12 Beat Rivals in 139 of 159 Heart-Rate Tests

3 articles · Updated · 9to5Mac · Sep 11

Summary

  • Apple released a nine-page study saying Apple Watch Series 12 delivered statistically better heart-rate accuracy than every rival device it tested in workouts and daily use.
  • 1,460 adults were enrolled across five U.S. and Malaysia sites in July and August 2026, with 1,254 contributing paired measurements against a Polar H10 ECG chest strap reference.
  • Series 12 was tested against Garmin Forerunner 970, Google Pixel Watch 4, Huawei Watch 5, Samsung Galaxy Watch 8, WHOOP 5 and Oura Ring 5 across running, cycling, HIIT, strength training and everyday activities.
  • Apple said the new Health Sensing System—updated electrical and optical sensors plus signal-processing algorithms—helped the watch outperform rivals in 139 of 159 activity and measurement comparisons.
  • The study supports Apple's marketing claim ahead of the Sept. 18 launch; Series 12 starts at $399 and Apple Watch Ultra 4 at $799.

Insights

Apple's self-funded study claims total dominance, but will upcoming independent tests expose hidden flaws in these sensors?
Can Apple's new algorithm truly eliminate cadence lock, or will serious athletes still need traditional chest straps?
With Apple Intelligence and a Quest partnership, is the Series 12 quietly trying to replace your primary care doctor?