Apple Watch Series 12 Starts at $399, Ships Sept. 18
Hardware / news
Apple Watch Series 12 Starts at $399, Ships Sept. 18
The update adds heart rate sensing every 5 seconds and a 0-to-10 daily "Readiness" score, but Apple has not said how it validated either claim.
Apple began taking preorders Wednesday for the Watch Series 12, which starts at $399 and measures heart rate every 5 seconds throughout the day instead of at intervals, the company said. The Watch Ultra 4, Apple's rugged variant, starts at $799 and ships the same day.
Kaiann Drance, Apple's vice president of worldwide Apple Watch product marketing, said the Series 12 is "the most advanced health and fitness companion we've ever created." Both watches go on sale in stores Friday, Sept. 18, in the US, UK, Canada, Australia, Japan, India and more than 50 other countries. WatchOS 27, which the new software features require, ships Monday, Sept. 14.
What the Health Sensing System actually measures
The headline feature is continuous heart rate: the Series 12 and Ultra 4 sample every 5 seconds around the clock, not just during workouts, and measure heart rate variability up to 24 times more often than the Series 11. Apple splits that variability reading into two scores, Recovery HRV and an overall HRV figure, and tracks both during the day and overnight.
A new Readiness score folds recent activity, training load, vitals and sleep into a single 0-to-10 number each morning, paired with one of four labels: Recover, Pace Yourself, Ready or Go For It. Apple's release does not say which of the four inputs is weighted most heavily, or publish a validation study against a clinical heart rate monitor.
The S11 chip and the battery trade-off
Both watches run a new S11 chip, which Apple says is its fastest wearable processor to date; the company did not publish clock speed, core count or a benchmark score, following the same pattern as Intel's Crescent Island GPU, which shipped in August without a published tokens-per-watt figure of its own.
The Series 12 holds 24 hours of everyday battery life, unchanged from the Series 11, but outdoor workout time rises 25 percent to 10 hours, and a 15-minute charge now delivers 12 hours of use, up 50 percent from the prior generation. The Ultra 4 goes further: 50 hours of everyday use, 84 hours in Low Power Mode, and up to 45 hours in Max Extended Workout mode with GPS running. A 15-minute charge on the Ultra 4 adds 18 hours.
Audio Intelligence needs the new hardware
Apple is gating four features behind the Series 12 and Ultra 4 specifically: Sound Recognition for deaf and hard-of-hearing users, a Live Rewind that replays the previous 15 seconds of audio, Siri Recap conversation summaries, and a faster version of Shazam's song identification. None of them run on the Series 11 or earlier.
Apple's announcement does not say whether audio captured for Live Rewind is processed on the watch or leaves the device. That question mattered for a rival product this week: Meta's Muse smart glasses shipped with a Secure VM Meta marketed as protected, only for the company's own engineering vice president to say staff access to a user's session is technically possible. Apple has not said which model applies to its own audio buffer.
Price, materials and what stayed the same
The Series 12 starts at $399 for a 42mm aluminum case and comes in 42mm and 46mm sizes; Apple has not changed the watch's case design since the Series 10 shipped in 2024. It adds Ceramic Shield 2 to the display, which Apple says is 60 percent tougher than the Ion-X glass it replaces. Buyers can also choose titanium or ceramic cases, and a Hermès edition returns in radiant gold titanium with a new Rocabar Club band.
The Ultra 4 stays titanium-only, in natural or black finishes, and keeps the satellite features Apple has offered since the Ultra 3: Emergency SOS, Find My and Messages via satellite, free for two years. Apple's release also touts "the most accurate on-device GPS in a sports watch," a claim the company did not attach to any independent test.
Two rumored features did not ship. Macworld managing editor Karen Haslam wrote after the announcement that Apple did not add the Touch ID fingerprint sensor some reports had predicted, and that the Series 12 still has no blood-glucose sensor.
Apple did not announce an update to the Watch SE alongside the Series 12 and Ultra 4. The next concrete date to watch is Sept. 14, when watchOS 27 ships and the Readiness score and Audio Intelligence features actually turn on.
Sources
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