Apple Watch Series 12 Debuts Health Sensing System

Apple Inc. (NASDAQ: AAPL) introduced the Apple Watch Series 12 on 9 September with a rebuilt sensor package the company calls the Health Sensing System, positioning measurement frequency rather than new metrics as the generational advance.

The watch runs on the S11 chip, which draws its CPU, graphics and Neural Engine components from the A20 Pro silicon used in the iPhone 18 Pro. Apple re architected the optical and electrical heart sensors and moved to more power efficient green light emitting diodes, allowing the watch to sample heart rate every five seconds through the day.

Heart rate variability readings can be taken up to 24 times more frequently than on the previous generation, with separate values reported for recovery and for overall HRV. Apple increased the electrode surface area to improve skin contact during ECG recordings, and says the result is the most accurate heart rate sensing it has shipped in a wearable. Step tracking has also been revised.

The Series 12 comes in 42mm and 46mm sizes across aluminium, titanium and ceramic cases. Aluminium models carry Ceramic Shield 2 front glass, which Apple says is 60% tougher than the Ion-X glass it replaces. Aluminium finishes include space gray, black, light gold and bronze.

Pricing starts at $399 for the 42mm aluminium GPS model, unchanged from the Series 11. Pre orders opened on 9 September across more than 50 countries and regions, with retail availability from 18 September.

Battery life remains rated at 24 hours, with faster charging.