Apple Watch Series 4 vs Apple Watch Ultra 4

Every spec side by side, from each maker's published figures.

Better figure, where one is clearly better

Watch Series 4 compared with Watch Ultra 4
AppleWatch Series 4AppleWatch Ultra 4
Overview
ReleasedSeptember 2018September 2026
Display
Case sizes40 mm or 44 mm49 mm
PanelLTPO OLEDLTPO OLED
Peak brightness1,000 nits3,000 nits (better)
Always-on displayNoYes
Display detailRetina LTPO OLED with Force Touch; 40mm 324 x 394 pixels and 759 sq mm; 44mm 368 x 448 pixels and 977 sq mm; display wakes by wrist raise (PhoneArena)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–Flat sapphire crystal front
Health and fitness
ECGYesYes
Blood oxygenNoYes
Skin temperatureNoYes
Sleep apnoea alertsNoYes
High blood pressure alertsNoYes
Body compositionNoNo
Fall detectionYesYes
Crash detectionNoYes
GPSSingle-bandDual-band (L1 and L5)
Water resistance50 m100 m (better)
SensorsElectrical and optical heart sensors; barometric altimeter; accelerometer up to 32 g-forces, improved gyroscope and ambient light sensorHealth 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 featuresECG capability, high and low heart-rate alerts and irregular-rhythm notifications; ECG app was not available at hardware launch and reached the UK in March 2019Readiness 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 featuresGPS, GLONASS, Galileo and QZSS; swimming, yoga and hiking workouts, automatic workout reminders, cadence, pace alerts and rolling mile pace in watchOS 5; GymKitCustomisable 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 featuresHard-fall detection can call emergency services after immobility and notify emergency contacts; Emergency SOSEmergency 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)Up to 18 hoursUp to 50 hours
In low-power mode–Up to 84 hours
Mobile data optionYesYes
Works withiPhoneiPhone
ChipS4S11
Storage16 GB64 GB (better)
Battery life detailBuilt-in rechargeable lithium-ion batteryUp 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
ChargingMagnetic charging cable and USB power adapterFast 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
ConnectivityW3 wireless chip; Wi-Fi 802.11b/g/n at 2.4GHz; Bluetooth 5.0; cellular versions add LTE and UMTS with a compatible plan; GPS requires iPhone 5s, cellular iPhone 6, both with iOS 12 at launchGPS + 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)30.1 g (better)63 g
SoftwarewatchOSwatchOS
Case materialsAluminium or stainless steel case; ceramic and sapphire crystal back; water resistance under ISO 22810:2010 for shallow-water swimmingGrade 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
Size40mm 40 x 34 x 10.7 mm, 30.1 g aluminium or 39.8 g steel; 44mm 44 x 38 x 10.7 mm, 36.7 g aluminium or 47.9 g steel; weights exclude bands49 x 44 x 12 mm; 63.0 g (natural) or 63.1 g (black)
BandsCompatible with earlier Apple Watch bands of the corresponding size; Nike+ includes Nike bands and watch faces; Hermès includes leather bands and exclusive faces. Nike+ became available 5 October 2018Fits 130–210 mm wrists
ColoursSilver, Space Grey and Gold aluminium; Silver, Space Black (DLC) and Gold (PVD) stainless steel; Nike+ Silver or Space Grey; Hermès polished stainless steelNatural or Black titanium
In the boxWatch and band, magnetic charging cable and USB power adapterApple Watch Ultra 4, strap, Apple Watch Magnetic Fast Charger to USB-C Cable (1 m)

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