Apple Watch Series 12 vs Apple Watch Ultra 4

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Watch Series 12 compared with Watch Ultra 4

	AppleWatch Series 12	AppleWatch Ultra 4
Overview
Released
Released	September 2026	September 2026
Display
Case sizes
Case sizes	42 mm or 46 mm	49 mm
Panel
Panel	LTPO OLED	LTPO OLED
Peak brightness
Peak brightness	2,000 nits	3,000 nits (better)
Always-on display
Always-on display	Yes	Yes
Display detail
Display detail	Always-On Retina display with wide-angle OLEDs and LTPO3; 1Hz refresh; 374 x 446 pixels (42mm) or 416 x 496 pixels (46mm) at 326 ppi; 970 or 1,196 sq mm display area; 1 nit minimum brightness	Always-On Retina display with wide-angle OLEDs and LTPO3; 1Hz refresh; 422 x 514 pixels at 326 ppi; 1,245 sq mm display area; 1 nit minimum brightness; Night Mode for Ultra watch faces
Screen protection
Screen protection	Ceramic Shield 2 (aluminium cases); sapphire front crystal (titanium and ceramic cases)	Flat sapphire crystal front
Health and fitness
ECG
ECG	Yes	Yes
Blood oxygen
Blood oxygen	Yes	Yes
Skin temperature
Skin temperature	Yes	Yes
Sleep apnoea alerts
Sleep apnoea alerts	Yes	Yes
High blood pressure alerts
High blood pressure alerts	Yes	Yes
Body composition
Body composition	No	No
Fall detection
Fall detection	Yes	Yes
Crash detection
Crash detection	Yes	Yes
GPS
GPS	Single-band	Dual-band (L1 and L5)
Water resistance
Water resistance	50 m	100 m (better)
Sensors
Sensors	Health Sensing System with third-generation electrical heart sensor, always-on optical heart sensor, blood oxygen sensor and temperature sensor; compass; always-on altimeter; high-g accelerometer; high dynamic range gyroscope; ambient light sensor; depth gauge to 6 m; water temperature sensor	Health Sensing System with third-generation electrical heart sensor, always-on optical heart sensor, blood oxygen sensor and temperature sensor; depth gauge to 40 m; water temperature sensor; compass; always-on altimeter (–500 m to 9,000 m); high-g accelerometer; high dynamic range gyroscope; ambient light sensor
Health features
Health features	Readiness app; Vitals app (heart rate, respiratory rate, wrist temperature, blood oxygen, sleep duration and HRV); Recovery HRV; high-frequency background heart rate tracking; ECG app; Blood Oxygen app; irregular rhythm notifications; high and low heart rate notifications; hypertension notifications; sleep apnoea notifications; sleep stages and sleep score; Cycle Tracking with fertile window and retrospective ovulation estimates, perimenopause and menopause support; Medications; Mindfulness; Noise	Readiness app; Vitals app (heart rate, respiratory rate, wrist temperature, blood oxygen, sleep duration and HRV); Recovery HRV; high-frequency background heart rate tracking; ECG app; Blood Oxygen app; irregular rhythm notifications; high and low heart rate notifications; hypertension notifications; sleep apnoea notifications; sleep stages and sleep score; Cycle Tracking with fertile window and retrospective ovulation estimates, perimenopause and menopause support; Medications; Mindfulness; Noise
Fitness features
Fitness features	Custom workouts; Training Load; customisable heart rate zones; VO2 max; Race Route; Pacer; cadence, stride length, ground contact time, vertical oscillation and running power; automatic track detection; multisport workouts; offline maps with custom route creation; Backtrack; pool and open-water swimming with SWOLF; cycling power zones with Bluetooth accessories; GymKit	Customisable Action button with Precision Start; custom workouts; Training Load and Workout Effort; customisable heart rate zones; VO2 max; Race Route; Pacer; cadence, stride length, ground contact time, vertical oscillation and running power; multisport workouts; offline maps with custom route creation; elevation alerts; Backtrack; swimming with water temperature; recreational diving to 40 m with Depth app and third-party dive computer apps; cycling with power meters; GymKit
Safety features
Safety features	Emergency SOS; international emergency calling; Fall Detection; Crash Detection; Check In; Backtrack; Last Emergency Call Availability Waypoint; torch; noise monitoring	Emergency SOS and Find My via satellite; Emergency SOS; international emergency calling; Siren; Fall Detection; Crash Detection; Check In; Backtrack; Last Emergency Call Availability Waypoint; torch; noise monitoring
Battery and connections
Battery life (maker's claim)
Battery life (maker's claim)	Up to 24 hours	Up to 50 hours
In low-power mode
In low-power mode	Up to 38 hours	Up to 84 hours
Mobile data option
Mobile data option	Yes	Yes
Works with
Works with	iPhone	iPhone
Chip
Chip	S11	S11
Storage
Storage	64 GB	64 GB
Battery life detail
Battery life detail	Up to 24 hours of normal use; up to 38 hours in Low Power Mode; up to 10 hours of outdoor workout	Up to 50 hours of normal use; up to 84 hours in Low Power Mode; up to 18 hours of outdoor workout, 25 hours in Extended Workout and 45 hours in Max Extended Workout
Charging
Charging	Fast charging to 80% in about 30 minutes; 15 minutes for up to 12 hours of normal use; 5 minutes for up to 10 hours of sleep tracking	Fast charging to 80% in about 45 minutes; 15 minutes for up to 18 hours of normal use; 5 minutes for up to 10 hours of sleep tracking
Connectivity
Connectivity	Wi-Fi 4 (802.11n) at 2.4GHz and 5GHz; Bluetooth 5.3; second-generation Ultra Wideband chip; NFC for Apple Pay; Precision L1 GPS (GPS, GLONASS, Galileo, QZSS and BeiDou); GPS + Cellular models (A3582, A3587) with 5G RedCap and LTE	GPS + Cellular only (model A3579) with 5G RedCap and LTE; satellite communications; Wi-Fi 4 (802.11n) at 2.4GHz and 5GHz; Bluetooth 5.3; second-generation Ultra Wideband chip; NFC for Apple Pay; precision dual-frequency GPS (GPS, Galileo, QZSS and BeiDou)
Design
Weight (lightest version)
Weight (lightest version)	31.5 g (better)	63 g
Software
Software	watchOS	watchOS
Case materials
Case materials	100% recycled aluminium or 3D-printed 100% recycled titanium case with zirconia back, or ceramic case; water resistant to 50 m (ISO 22810:2010); IP6X dust resistant	Grade 5 titanium case (100% recycled titanium) with ceramic and zirconia back; water resistant to 100 m (ISO 22810:2010); EN13319 recreational diving to 40 m; IP6X dust resistant; tested to MIL-STD 810H
Size
Size	42mm is 42 x 37 x 9.7 mm (ceramic 43 x 37 x 9.85 mm); 46mm is 46 x 40 x 9.7 mm (ceramic 47 x 41 x 9.85 mm); lightest is the 42mm aluminium GPS + Cellular at 31.5 g, heaviest the 46mm Night Blue ceramic at 52.9 g	49 x 44 x 12 mm; 63.0 g (natural) or 63.1 g (black)
Bands
Bands	Fits 130–200 mm wrists (42mm) or 140–245 mm wrists (46mm)	Fits 130–210 mm wrists
Colours
Colours	Aluminium in Dark Bronze, Light Gold, Black and Space Grey; titanium in Radiant Gold and Natural; ceramic in Pearl White and Night Blue	Natural or Black titanium
In the box
In the box	Apple Watch Series 12, strap, Apple Watch Magnetic Fast Charger to USB-C Cable (1 m)	Apple Watch Ultra 4, strap, Apple Watch Magnetic Fast Charger to USB-C Cable (1 m)