Apple Watch Series 12 keeps the $399 starting price, the 42mm and 46mm sizes and the 24-hour battery rating of last year’s Series 11. What changes is the S11 chip, a new Health Sensing System, a tougher front crystal, a ceramic case option, faster charging and a set of on-watch audio features.
Apple positions Series 12 as a health upgrade rather than a redesign, and the spec sheet reflects that. Our Series 12 preview covers what was expected before the keynote.
Apple Watch Series 12 vs Series 11 specs
| Spec | Series 12 | Series 11 |
|---|---|---|
| Starting price | $399 | $399 |
| Sizes | 42mm, 46mm | 42mm, 46mm |
| Chip | S11, with Secure Exclave | S10 |
| Front crystal (aluminum) | Ceramic Shield 2 | Ion-X glass |
| Case materials | Aluminum, titanium, ceramic | Ceramic not offered |
| Heart rate sampling | Every 5 seconds | Not stated by Apple |
| HRV sampling | Every 5 minutes, 24 times more often | Less frequent |
| All-day battery | Up to 24 hours | Up to 24 hours |
| Low Power Mode | Not published | Up to 38 hours |
| Charging | 15 minutes for 12 hours | Not published |
7 differences between Series 12 and Series 11
- S11 chip: Apple calls it its most powerful wearable chip, and it adds a Secure Exclave, a hardware-isolated area for on-device audio processing with immediate deletion
- Health Sensing System: new optical and electrical heart sensors, heart rate every 5 seconds and HRV every 5 minutes, with a new Recovery HRV measure and daytime vitals view
- Readiness score: a daily 0 to 10 rating from activity, training load, vitals and sleep, with Recover, Pace Yourself, Ready and Go For It recommendations
- Ceramic Shield 2: aluminum models get a front crystal Apple says is 60 percent tougher than the Ion-X glass on Series 11 aluminum
- Ceramic case: a new material in pearl white and night blue, alongside four aluminum and two titanium finishes
- Workouts and charging: outdoor workout tracking rises 25 percent to 10 hours, and 15 minutes of charging now gives 12 hours, 50 percent faster than before
- Audio Intelligence: Sound Recognition alerts, Live Rewind for the last 15 seconds of conversation as text, Siri Recap summaries and Shazam detection, all on the watch
What stays the same
Price, sizes and all-day battery life are unchanged, and Series 11 already had 5G on cellular models. Apple has not published display specifications for Series 12, so there is no basis for claiming a brighter or larger screen.
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Series 11 also gets watchOS 27 on Monday, September 14, the same day as iOS 27, including Siri AI in beta, the dynamic app grid, the single-handed tap gesture and the Cycle Tracking perimenopause features. Those are software, not Series 12 exclusives.
Should you upgrade from Series 11?
If you bought a Series 11 in the past year, the case for Series 12 rests on the sensors. Heart rate every 5 seconds, HRV every 5 minutes and the Readiness score are hardware-dependent, and Apple has not said whether Readiness or Audio Intelligence will reach the S10 through software.
If those features do not matter to you, watchOS 27 brings Series 11 most of this year’s software. The stronger upgrade case is for watches older than Series 9, which is the cutoff for watchOS 27.
Series 12 is available to pre-order now and reaches stores on Friday, September 18. Apple did not announce a new Apple Watch SE despite the SE 3 going unavailable before the event, and it has not published Low Power Mode hours, weight or titanium and ceramic prices for Series 12.
