Samsung Galaxy Watch Ultra vs Samsung Galaxy Watch8

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Galaxy Watch Ultra compared with Galaxy Watch8

	SamsungGalaxy Watch Ultra	SamsungGalaxy Watch8
Overview
Released
Released	July 2024	July 2025
Display
Case sizes
Case sizes	47 mm	40 mm or 44 mm
Panel
Panel	OLED	OLED
Peak brightness
Peak brightness	3,000 nits	3,000 nits
Always-on display
Always-on display	Yes	Yes
Display detail
Display detail	Super AMOLED with full-colour Always On Display; 1.5-inch (37.3 mm) with 480 x 480 pixels; 16M colours; Night Mode on its own watch faces	Super AMOLED with full-colour Always On Display; 40 mm has 1.34 inches (34 mm) with 438 x 438 pixels; 44 mm has 1.47 inches (37.3 mm) with 480 x 480 pixels; 16M colours
Screen protection
Screen protection	Sapphire Crystal	Sapphire Crystal
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	No	No
Body composition
Body composition	Yes	Yes
Fall detection
Fall detection	Yes	Yes
Crash detection
Crash detection	No	No
GPS
GPS	Dual-band (L1 and L5)	Dual-band (L1 and L5)
Water resistance
Water resistance	100 m (better)	50 m
Sensors
Sensors	Samsung BioActive Sensor (optical bio-signal sensor, electrical heart signal sensor and bioelectrical impedance analysis sensor); temperature sensor; accelerometer; barometer; gyro sensor; geomagnetic sensor; light sensor	Samsung BioActive Sensor (optical bio-signal sensor, electrical heart signal sensor and bioelectrical impedance analysis sensor); infrared temperature sensor; accelerometer; barometer; gyro sensor; geomagnetic sensor; light sensor
Health features
Health features	ECG with Irregular Heart Rhythm Notification, blood pressure (calibrated against an arm cuff every 4 weeks) and sleep apnoea detection in the Samsung Health Monitor app, which needs a Galaxy phone; AGEs Index; sleep analysis; body composition; heart rate alerts	ECG with Irregular Heart Rhythm Notification, blood pressure (calibrated against an arm cuff every 4 weeks) and CE-marked sleep apnoea detection in the Samsung Health Monitor app, which needs a Galaxy phone; Antioxidant Index; Energy Score; Bedtime Guidance and Sleep Coaching; Vascular Load; body composition; stress tracking and guided meditation; Cycle Tracking
Fitness features
Fitness features	Multi-sports tile for triathlons; Functional Threshold Power (FTP) for cycling in 4 minutes; Personalised Heart Rate Zone; Quick Button to start and control workouts; works from 500 m below sea level to 9,000 m altitude	Running Coach; automatic workout detection
Safety features
Safety features	Emergency Siren up to 86 dB, heard up to 180 m away (hold the Quick Button); Emergency SOS; Fall Detection	Emergency SOS; Fall Detection
Battery and connections
Battery life (maker's claim)
Battery life (maker's claim)	Up to 60 hours	Up to 30 hours
In low-power mode
In low-power mode	Up to 100 hours	–
Mobile data option
Mobile data option	Yes	Yes
Works with
Works with	Android	Android
Chip
Chip	Exynos W1000	Exynos W1000
Storage
Storage	32 GB	32 GB
Battery life detail
Battery life detail	Up to 60 hours with Always On Display on and up to 80 hours with it off; up to 100 hours in Power Saving; up to 48 hours of outdoor workout with GPS in Exercise Power Saving; 590 mAh typical capacity	Up to 30 hours with Always On Display on and up to 40 hours with it off; 325 mAh (40 mm) and 435 mAh (44 mm) typical capacity
Charging
Charging	Fast Charging (WPC-based wireless charging)	Fast Charging (WPC-based wireless charging); wireless charger in the box
Connectivity
Connectivity	LTE with eSIM (4G LTE and 3G); Bluetooth 5.3; Wi-Fi 802.11a/b/g/n at 2.4 GHz and 5 GHz; NFC; L1 + L5 dual-frequency GPS with Glonass, Beidou and Galileo; pairs with Android 11 or later phones with more than 1.5 GB of memory	LTE models with eSIM (4G LTE and 3G); Bluetooth 5.3; Wi-Fi 802.11a/b/g/n at 2.4 GHz and 5 GHz; NFC; L1 + L5 dual-frequency GPS with Glonass, Beidou and Galileo; pairs with Android 12 or later phones with more than 1.5 GB of memory
Storage
Storage	2 GB memory; 32 GB storage (21.1 GB available); the Galaxy Watch Ultra (2025), sold from July 2025, has 64 GB (50.0 GB available)	2 GB memory; 32 GB storage (20.2 GB available on the 44 mm Bluetooth model)
Design
Weight (lightest version)
Weight (lightest version)	60.5 g	30 g (better)
Software
Software	Wear OS	Wear OS
Case materials
Case materials	Grade 4 titanium on the front and back cover areas of the frame, the rest a mix of plastic and grade 2 titanium; Sapphire Crystal; 10ATM and IP68; MIL-STD-810H; works on the wrist from -20°C to 55°C	Armor Aluminium case; Sapphire Crystal; 5ATM and IP68; MIL-STD-810H
Size
Size	47.1 x 47.4 x 12.1 mm; 60.5 g (watch body without band)	40 mm is 42.7 x 40.4 x 8.6 mm and 30.0 g; 44 mm is 46.0 x 43.7 x 8.6 mm and 34.0 g (watch body without band)
Bands
Bands	–	Dynamic Lug System; Sport, Fabric, Hybrid and Athleisure bands
Colours
Colours	Titanium Silver, Titanium Gray, Titanium White; the 2025 version adds Titanium Blue	Graphite, Silver