The Apple Watch Series 12 is now available, bringing a familiar exterior together with updated health sensors, a faster chip, and improved charging. Although the design closely matches the Series 11, Apple has changed the materials, internal hardware, and health-tracking system beneath the surface.

The new watch comes in 42mm and 46mm sizes, with prices starting at $399. Its aluminum models are offered in light gold, dark bronze, black, and space gray. Ceramic versions come in pearl white and night blue, while polished titanium models are available in radiant gold and natural.

A familiar design with tougher front glass

From the front, the Series 12 is difficult to distinguish from the Series 11. The most visible external changes are the new color choices. Apple is also replacing Ion-X glass on the aluminum models with Ceramic Shield 2, which it says is 60 percent tougher.

The back of the watch has received a more substantial update. Apple has redesigned the sensor area as part of what it calls the Health Sensing System, pairing the new sensors with the S11 chip. The company says the combination makes the Series 12 its most accurate wearable for heart-rate sensing.

More frequent health measurements

The Series 12 now checks heart rate every five seconds and measures heart-rate variability as often as every five minutes. Those higher sampling rates support a new readiness score, which helps indicate whether the wearer should push harder with activity or take a rest day.

The score uses recent activity, vital signs, and sleep data, then changes as the day progresses. It takes roughly a week of data collection on the Series 12 before the feature begins providing a readiness score.

Battery life and charging

Despite the additional measurements, the watch remains rated for all-day battery life. Early use did not show excessive battery drain from the higher sampling rates. Charging is faster, with up to 12 hours of normal use available after a 15-minute charge.

That faster rate requires the charger included with the Series 12. Older Apple Watch chargers do not provide the same charging performance, so owners upgrading from an earlier model may need to use the new accessory.

Should you upgrade?

The S11 chip also supports Live Rewind and Siri Recap, although Apple says those features will not arrive until later this year. Their delayed availability means the watch’s most immediate advantages are its sensor improvements, readiness tracking, tougher front glass, and faster charging.

For owners of an Apple Watch Series 10 or Series 11, the lack of a design refresh may make upgrading difficult to justify. Users with an older model stand to gain more from the Series 12’s updated health features and improved charging system.