Skip to content

Watch comparison

Apple Ultra 4 49mm vs Apple Series 12 42mm

Compare battery life, health tracking, display and fit.

Compared products
01Selected
Apple Watch Ultra 4 49mm

Apple Watch Ultra 4 49mm

  • 1.98 inch screen.
  • Apple S11 processor.
  • 64 GB storage in this version.
  • Runs watchOS 27.
  • Wi-Fi 4 support.
KSh 118,000In Stock
Choose options
02
Apple Watch Series 12 42mm

Apple Watch Series 12 42mm

  • Apple S11 chip; 4-core Neural Engine processor.
  • 64 GB storage in this version.
  • Runs watchOS 27.
  • Wi-Fi 4 support.
  • Touchscreen for direct touch input.
KSh 64,000In Stock
Choose options

Add to comparison

2 spaces available

Apple Watch Ultra 3KSh 90,000
Apple Watch Series 11KSh 51,000
Apple Watch Series 8KSh 50,000
Apple Watch UltraKSh 90,000
Apple Watch Ultra 2KSh 103,500
Huawei Watch Ultimate 2KSh 124,000
Amazfit T-Rex Ultra 2KSh 85,000
2 of 4 products

Our quick verdict

The Apple Watch Ultra 4 49mm lasts longer between charges (50 hours vs 24 hours), has a brighter screen for outdoor use and is rated for free diving to 40 m, while the Apple Watch Series 12 42mm is lighter to wear all day and has faster recharging (30 minutes).

Performance

Apple Watch Ultra 4 49mm
Apple S11 processor
Apple Watch Series 12 42mm
Apple S11 chip; 4-core Neural Engine processor

Battery life

Apple Watch Ultra 4 49mm
Up to 50 hours per charge
Apple Watch Series 12 42mm
Up to 24 hours per charge

Portability

Apple Watch Ultra 4 49mm
63 g
Apple Watch Series 12 42mm
32.2 g

Display

Apple Watch Ultra 4 49mm
1.98-inch OLED display, 326 ppi
Apple Watch Series 12 42mm
OLED display, 326 ppi

Water resistance

Apple Watch Ultra 4 49mm
100 m under ISO 22810:2010
Apple Watch Series 12 42mm
50 m swimproof under ISO 22810:2010

Key differences

The main differences to help you choose.

Apple Watch Ultra 4 49mm

  • Longer battery life: up to 50 hours (vs 24 hours).
  • Rated for up to 50 hours per charge (vs 24).
  • Longer sport-mode battery: up to 18 hours in workout tracking mode (vs 10 hours in outdoor workout mode).
  • Brighter display: up to 3,000 nits (vs 2,000).
  • Rated for free diving to 40 m.

Apple Watch Series 12 42mm

  • Lighter: 32.2 g (vs 63 g).
  • Recharges faster: 30 minutes (vs 45 minutes).
  • Slimmer: 9.7 mm thick (vs 12 mm).

What matters most to you?

Choose any priorities

How each product answers the questions buyers ask most. Tick a topic to add it, untick one to hide it.

More topicsFewer topics
6 priorities selected.
How each product answers the selected priorities
PriorityApple Watch Ultra 4 49mmApple Watch Series 12 42mm
Battery lifeUp to 50 hours per chargeUp to 24 hours per charge
Storage64 GB storage64 GB storage
Display1.98-inch OLED display, 326 ppiOLED display, 326 ppi
PerformanceApple S11 processorApple S11 chip processor
SoftwarewatchOS 27watchOS 27
Water resistance100 m under ISO 22810:201050 m swimproof under ISO 22810:2010

Detailed comparison

Explore the full specifications, section by section.

Display

Display specifications comparison
SpecificationApple Watch Ultra 4 49mmApple Watch Series 12 42mm
DisplayRetina LTPO3 OLED, 3000 nits (peak); 1.98 inchesAlways-On Retina LTPO3 wide-angle OLED
Screen resolution422 × 514 pixels; 326 ppi; 1,245 mm² display area42mm: 374 × 446 pixels, 970 mm² display area. 46mm: 416 × 496 pixels, 1196 mm² display area. Both: 326 ppi.
Display protectionSapphire crystalCeramic Shield 2 on aluminum cases; sapphire front crystal on titanium and ceramic cases
Display features3000 nits (peak); Wide-angle OLED1 Hz refresh; up to 2,000 nits peak brightness; 1 nit minimum brightness

Connectivity

Connectivity specifications comparison
SpecificationApple Watch Ultra 4 49mmApple Watch Series 12 42mm
Network / cellularGSM / HSPA / LTE / 5G5G RedCap and LTE on GPS + Cellular models; international roaming supported
SIM / eSIMeSIMeSIM on GPS + Cellular models
Wi-FiWi-Fi 802.11 b/g/n, dual-bandWi‑Fi 4 (802.11n), 2.4 GHz and 5 GHz
Bluetooth5.3, A2DP, LEBluetooth 5.3
NFCYesSupported; Apple Pay
Positioning / GNSSGPS (L1+L5), GLONASS, GALILEO, BDS, QZSSPrecision L1 GPS; GLONASS; Galileo; QZSS; BeiDou
Ultra Wideband (UWB)Ultra Wideband (UWB) support (gen2 chip)Second-generation Ultra Wideband chip
Satellite featuresEmergency SOS via satellite—

Identity & design

Identity & design specifications comparison
SpecificationApple Watch Ultra 4 49mmApple Watch Series 12 42mm
BrandAppleApple
ModelApple Watch Ultra 4 49mmApple Watch Series 12 (42mm and 46mm configurations)
Announced2026, September 099 September 2026
Dimensions49 x 44 x 12 mm (1.93 x 1.73 x 0.47 in)42mm: aluminum/titanium 42 × 37 × 9.7 mm; ceramic 43 × 37 × 9.85 mm. 46mm: aluminum/titanium 46 × 40 × 9.7 mm; ceramic 47 × 41 × 9.85 mm.
WeightNatural titanium: 63.0 g; black titanium: 63.1 g42mm: aluminum GPS 32.2 g, GPS + Cellular 31.5 g, titanium 36.5 g, ceramic Pearl White 41.7 g / Night Blue 42.8 g. 46mm: aluminum GPS 39.5 g, GPS + Cellular 38.6 g, titanium 44.9 g, ceramic Pearl White 51.3 g / Night Blue 52.9 g.
Build materialsGrade 5 titanium case; sapphire crystal front; ceramic and sapphire crystal backAluminum, titanium or ceramic case, depending on configuration
Wrist size130–210 mm42mm: 130–200 mm; 46mm: 140–245 mm
Strap / bandIncluded band; style depends on the selected configurationBand supplied; material and size depend on the selected configuration
Controls / buttonsCustomizable Action button; Digital Crown with haptic feedback; side button; single tap, double tap and wrist flick gesturesDigital Crown with haptic feedback; side button; band-release button; single tap, double tap and wrist flick gestures

Performance & software

Performance & software specifications comparison
SpecificationApple Watch Ultra 4 49mmApple Watch Series 12 42mm
ProcessorApple S11Apple S11 chip; 4-core Neural Engine
CPUDual-core64-bit dual-core
GPUPowerVR—
Storage64GB64 GB
Operating systemwatchOS 27watchOS 27

Audio & communication

Audio & communication specifications comparison
SpecificationApple Watch Ultra 4 49mmApple Watch Series 12 42mm
SpeakerDual speakers; media playback; sirenSpeaker with media playback
MicrophoneThree-microphone array with beamforming and wind-noise mitigationMicrophone with Voice Isolation
CallingCellular and Bluetooth calling; international emergency callingBluetooth calling; cellular calling on GPS + Cellular models; international emergency calling

Sensors, health & fitness

Sensors, health & fitness specifications comparison
SpecificationApple Watch Ultra 4 49mmApple Watch Series 12 42mm
SensorsElectrical heart sensor; always-on optical heart sensor; blood oxygen sensor; temperature sensor; depth gauge; water-temperature sensor; compass; always-on altimeter; high-g accelerometer; high dynamic-range gyroscope; ambient-light sensorHigh-g accelerometer; high dynamic-range gyroscope; compass; always-on altimeter; ambient-light sensor; second-generation electrical heart sensor; always-on optical heart sensor; blood-oxygen sensor; temperature sensor; depth gauge; water-temperature sensor
Health & wellness featuresHeart rate; HRV; blood oxygen; ECG; wrist temperature; respiratory rate; Readiness; Vitals; cycle tracking; high/low heart-rate, irregular rhythm and hypertension notifications (regional availability)Heart rate and HRV; Blood Oxygen; ECG; respiratory rate; wrist temperature; Readiness and Vitals; high/low heart-rate and irregular-rhythm notifications; cycle tracking; hypertension notifications
Sleep trackingSleep duration; sleep stages; sleep score; sleep-apnea notifications (regional availability)Sleep duration and stages; sleep score; sleep-apnea notifications
Sports / workout modesRunning; hiking; cycling; pool and open-water swimming; skiing; snowboarding; rowing; paddling; golf; walking; HIIT; yoga; strength; dance; Pilates; Tai Chi; kickboxing; multisport and moreRunning; hiking; cycling; pool and open-water swimming; skiing; snowboarding; rowing; paddling; golf; walking; HIIT; yoga; strength; dance; Pilates; Tai Chi; kickboxing; multisport and more
Training & outdoor featuresCustom workouts and views; Training Load and Workout Effort; heart-rate zones; VO₂ max; Race Route; Pacer; running dynamics; automatic track detection; offline maps, routes, waypoints, Backtrack and elevation alertsCustom workouts and views; Training Load; heart-rate zones; VO₂ max; Race Route; Pacer; running dynamics; automatic track detection; offline maps, routes, waypoints and Backtrack
Safety & emergency featuresEmergency SOS; satellite SOS and messaging; international emergency calling; siren; flashlight; Fall Detection; Crash Detection; Check In; noise monitoring; emergency waypointsEmergency SOS; international emergency calling; Fall Detection; Crash Detection; flashlight; Check In; noise monitoring; emergency waypoints
Diving / depth featuresRecreational scuba diving to 40 m; automatic dive launch at 1 m; current/maximum depth and duration; GPS entry/exit points; depth gauge and water temperatureDepth gauge to 6 m; water-temperature sensor

Battery & durability

Battery & durability specifications comparison
SpecificationApple Watch Ultra 4 49mmApple Watch Series 12 42mm
Battery capacityLi-Ion 631 mAh—
Battery lifeUp to 50 hours normal use; 84 hours Low Power Mode; 18 hours workout tracking; 25 hours Extended Workout; 45 hours Max Extended WorkoutUp to 24 hours normal use; up to 38 hours Low Power Mode; up to 10 hours outdoor workout
ChargingMagnetic fast charging; up to 80% in about 45 minutesFast-charge capable; up to 80% in about 30 minutes; 15 minutes for up to 12 hours normal use; 5 minutes for up to 10 hours sleep tracking
Water resistance100 m under ISO 22810:2010; suitable for swimming, snorkeling, scuba and high-speed water sports50 m swimproof under ISO 22810:2010
Durability / certificationsIP6X dust resistance under IEC 60529; EN 13319 recreational diving to 40 m; tested to MIL‑STD‑810HIP6X dust resistance

Compatibility

Compatibility specifications comparison
SpecificationApple Watch Ultra 4 49mmApple Watch Series 12 42mm
Phone compatibilityiPhone 11 or later, including iPhone SE (2nd generation or later), with iOS 27 or lateriPhone 11 or later, including iPhone SE (2nd generation or later), with iOS 27 or later
Companion appApple Watch app on iPhoneApple Watch app on iPhone; Health and Fitness apps for associated data
ColorsNatural, BlackAluminum: Dark Bronze, Light Gold, Black, Space Gray; titanium: Radiant Gold, Natural; ceramic: Pearl White, Night Blue

Additional specifications

Additional specifications specifications comparison
SpecificationApple Watch Ultra 4 49mmApple Watch Series 12 42mm
Case materialGrade 5 titanium—
Military-grade resistanceMIL-STD-810H—
FlashlightSupportedSupported
Display materialLTPO3 wide-angle OLEDLTPO3 wide-angle OLED
Pixels per inch326 ppi326 ppi
Peak brightnessUp to 3,000 nits peak; 1 nit minimumUp to 2,000 nits peak; 1 nit minimum
Cover / touchscreenSupportedSupported
Charging timeAbout 45 minutes to 80%; 15 minutes for up to 18 hours normal use; 5 minutes for up to 10 hours sleep trackingAbout 30 minutes to 80%; 15 minutes for up to 12 hours normal use; 5 minutes for up to 10 hours sleep tracking
Packing listApple Watch Ultra 4; band; 1 m magnetic fast-charger to USB-C cableApple Watch Series 12; band; 1 m magnetic fast-charger to USB-C cable
Release statusAvailable. Released 2026, September 18Available. Released 2026, September 18
Model numbersA3579A3582, A3587
Card slotNoNo
CameraNoNo
3.5 mm headphone jackNoNo
USBNoNo
RadioNoNo
2G bandsGSM 850 / 900 / 1800 / 1900GSM 850 / 900 / 1800 / 1900
3G bandsHSDPA 850 / 900 / 1700(AWS) / 1900 / 2100HSDPA 850 / 900 / 1700(AWS) / 1900 / 2100
4G bands1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 17, 18, 19, 20, 25, 26, 28, 38, 39, 40, 41, 53, 66, 711, 2, 3, 4, 5, 7, 8, 12, 13, 14, 17, 18, 19, 20, 25, 26, 28, 38, 39, 40, 41, 66, 71
5G bands1, 2, 3, 5, 7, 8, 12, 14, 20, 25, 26, 28, 38, 40, 41, 53, 66, 71 SA/NSA1, 2, 3, 5, 7, 8, 12, 14, 20, 25, 26, 28, 38, 40, 41, 66, 71 SA/NSA
Network speedHSPA, LTE, 5GHSPA, LTE, 5G
Additional hardware featuresHealth Sensing System: third‑generation electrical heart sensor, always‑on optical heart sensor, blood oxygen sensor, temperature sensor; Temperature sensing (0.01˚ accuracy); Depth gauge (±1m accuracy)Health Sensing System: third‑generation electrical heart sensor, always‑on optical heart sensor, blood oxygen sensor, temperature sensor; Temperature sensing (0.01˚ accuracy); Media playback

Similarities

  • Both belong to the Apple Watch platform.
  • Both support Wi-Fi 4.
  • Both use Bluetooth 5.3.
  • Both work with a companion app.
  • Both have NFC.
  • Both take ECG readings.

In summary

For most buyers the Apple Watch Ultra 4 49mm is the better buy; the Apple Watch Series 12 42mm makes sense if you want a lighter watch for all-day wear.

Back to compared products ↑

In-stock alternatives

Apple Watch Ultra 2For Apple Watch Ultra 4 49mmApple Watch Ultra 2View product ↗Apple Watch UltraFor Apple Watch Ultra 4 49mmApple Watch UltraView product ↗Samsung Galaxy Watch Ultra 2 47mmFor Apple Watch Series 12 42mmSamsung Galaxy Watch Ultra 2 47mmView product ↗Apple Watch Series 11For Apple Watch Series 12 42mmApple Watch Series 11View product ↗

Related comparisons

Apple Watch Ultra 3Apple Watch Ultra 4 49mmApple Watch Series 11Apple Watch Ultra 4 49mmApple Watch Series 8Apple Watch Ultra 4 49mmApple Watch UltraApple Watch Ultra 4 49mmApple Watch Ultra 2Apple Watch Ultra 4 49mmHuawei Watch Ultimate 2Apple Watch Ultra 4 49mmAmazfit T-Rex Ultra 2Apple Watch Ultra 4 49mmApple Watch Ultra 4 49mmApple Watch Series 12 46mmApple Watch Ultra 4 49mmHuawei Watch D3
Menu
Need Help? +254 112891117
Back to Top

My Cart