Apple unveiled the Apple Watch Series 12 featuring an all-new health-sensing system and the S11 chip. It adds what it called the most accurate heart-rate measurement in wearables, a readiness score and audio intelligence features for users with hearing impairment or hearing loss.

The new health-sensing system redesigns optical and electrical heart-rate sensors to support continuous, high-quality health monitoring. In Apple’s accuracy study of more than 1,000 people, Apple Watch recorded the highest heart-rate measurement accuracy among major wearable devices. It measures heart rate every 5 seconds throughout the day with a larger, more power-efficient green LED, and heart rate variability, an indicator of stress and recovery, is measured up to 24 times more often.

It also adds a "readiness" feature that indicates the next day’s physical condition in advance. It analyses recent activity and training load, vital signs and sleep score, and provides a score from 0 to 10 along with tailored recommendations such as "recovery needed", "pace yourself", "ready" and "peak". The score updates throughout the day whenever there is high-intensity exercise or a change in vital signs.

Battery life has also increased. It supports up to 24 hours for everyday use, and up to 10 hours for outdoor workouts, up 25 percent from the previous model. It also includes fast charging that provides up to 12 hours of use with a 15-minute charge.

An "audio intelligence" feature using the built-in microphone and the S11 chip also stands out. A "sound recognition" feature detects sirens, alarms, doorbells and a baby crying, among other sounds, even when an iPhone is not nearby, and notifies users with hearing impairment or hearing loss. It also integrates Shazam, which automatically recognises nearby music and displays the song title and artist in Smart Stack.

Apple explained that audio processing is performed in a dedicated hardware isolation area separated from the system, called Secure Exclave, and that it does not store recordings. Siri AI, provided with watchOS 27, is based on Apple Intelligence and enables personal context understanding and world knowledge on the wrist.

Kaiann Drance (카이앤 드랜스), Apple’s vice president of worldwide Apple Watch product marketing, said, "Apple Watch Series 12 is the most advanced health and fitness partner we have ever introduced." She added, "With the new health-sensing system and the S11 chip, it provides useful insights such as readiness to help users better understand how they manage their health."

The case comes in two sizes, 42 mm and 46 mm. The aluminium model will be released in four colours: dark bronze, black, light gold and space grey, and features Ceramic Shield 2, which is 60 percent more durable than the existing Ion-X glass. The titanium model comes in natural titanium and a new radiant gold colour, while the ceramic model comes in pearl white and night blue.

Apple Watch Series 12 starts at 599,000 won in South Korea. Pre-orders begin on the 11th, with official sales starting on the 18th. watchOS 27 will be available from the 14th on Apple Watch Series 9 and later models, SE 3, and Ultra 2 and later models. Siri AI will be offered in beta in English on the same day, and Korean is expected to be supported in October.