Apple Watch Ultra 2 vs Watch Ultra 4 specs comparison
Ultra 4 is the obvious choice when buying new, mainly because it brings a larger display, up to 50 hours of normal battery life, faster charging, Siri AI and newer health tools including Readiness and Recovery HRV. Ultra 2 remains very capable, though, so existing owners who are happy with its 36-hour battery life and current health features have less reason to upgrade.
Full comparison
The full record
77 specifications across 6 areas, with 18 genuine differences.
1. Design & display Mixed
Fact
Apple Watch Ultra 2
Apple Watch Ultra 4
Release date
2023-09-22
2026-09-18
Physical size
49 x 44 x 12 mm
49 x 44 x 12 mm
Weight
61.4 g (Natural), 61.8 g (Black)
63.0 g (Natural), 63.1 g (Black)
Material
Grade 5 titanium case
Grade 5 titanium case
Water resistance
10 ATM; IP6X; MIL-STD 810H; recreational scuba diving to 40 m
10 ATM; IP6X; MIL-STD 810H; recreational scuba diving to 40 m
Color options
Natural Titanium, Black Titanium
Natural Titanium, Black Titanium
Display type
Always-On Retina LTPO2 OLED
Always-On Retina LTPO3 wide-angle OLED
Display size
49 mm case
49 mm case
Display resolution
410 x 502 pixels
422 x 514 pixels
Display brightness
Up to 3,000 nits
Up to 3,000 nits
Display protection
Flat sapphire crystal display
Flat sapphire crystal display
2. Battery & charging Apple Watch Ultra 4
Fact
Apple Watch Ultra 2
Apple Watch Ultra 4
Battery
Rechargeable lithium-ion battery
Rechargeable lithium-ion battery
Battery life
Up to 36 hours; up to 72 hours in Low Power Mode
Up to 50 hours normal use; up to 84 hours in Low Power Mode; up to 18 hours outdoor workout; up to 25 hours Extended Workout; up to 45 hours Max Extended Workout
Charging
USB-C magnetic fast charging; up to 80% in about 1 hour
USB-C magnetic fast charging; up to 80% in about 45 minutes
3. Sensors & positioning No clear edge
Fact
Apple Watch Ultra 2
Apple Watch Ultra 4
GNSS type
Built-in dual-band GNSS
Built-in dual-band GNSS
GPS
Yes
Yes
GALILEO
Yes
Yes
GLONASS
Yes
No
QZSS
Yes
Yes
Beidou
Yes
Yes
Accelerometer
Yes
Yes
Gyroscope
Yes
Yes
Barometric altimeter
Yes
Yes
Compass
Yes
Yes
Ambient light sensor
Yes
Yes
Optical heart rate
Yes
Yes (always-on optical heart sensor; high-frequency background tracking)
Electrical heart rate
Yes
Yes
SpO2
Yes
Yes
Temperature
Yes
Yes
Galvanic skin response
No
No
Microphone
Yes
Yes
Speakers
Yes
Yes
Vibration motor
Yes
Yes
4. Health & activity Even
Fact
Apple Watch Ultra 2
Apple Watch Ultra 4
Steps
Yes
Yes
Distance
Yes
Yes
Calories burned
Yes
Yes
Floors
Yes
Yes
Sports tracking
Yes
Yes
Sleep
Yes
Yes
Heart rate
Yes
Yes
HRV
Yes
Yes (Up to 24x more frequent than Ultra 3)
Stress
No
No
Blood oxygen
Yes
Yes
Respiration rate
Yes
Yes
Skin temperature
Yes
Yes
ECG
Yes
Yes
Blood pressure
Hypertension notifications (no direct blood-pressure measurement)
Hypertension notifications (no direct blood-pressure measurement)
Body composition
No
No
Glucose
No
No
Hydration level
No
No
UV exposure
No
No
Calorie intake
No
No
Hyperglycemia risk assessment
No
No
Arterial stiffness detection
No
No
Pulse wave arrhythmia analysis
Yes
Yes
No significant differences in this area.
5. Smart features No clear edge
Fact
Apple Watch Ultra 2
Apple Watch Ultra 4
Smartphone compatibility
iPhone Xs or later with iOS 17 or later at launch
iPhone 11 or later or iPhone SE (2nd generation or later) with iOS 27 or later
Operating system at launch
watchOS
watchOS 27
Processor
Apple S9, 64-bit dual-core; 4-core Neural Engine
Apple S11, 64-bit dual-core processor; 4-core Neural Engine; Audio Intelligence
Storage
64 GB
64 GB
Bluetooth
Yes (5.3)
Yes (5.3)
Wi-Fi
Yes (Wi-Fi 4 / 802.11n)
Yes (Wi-Fi 4 / 802.11n, 2.4/5 GHz)
NFC / connected pay
Yes (Apple Pay)
Yes (Apple Pay)
UWB
Yes (2nd-generation UWB)
Yes (2nd-generation UWB)
Cellular
Yes (LTE/UMTS)
Yes (5G RedCap and LTE on supported regional models)
Smartphone notifications
Yes
Yes
Bluetooth calling
Yes (standalone on cellular models; via paired iPhone otherwise)
Yes (standalone on cellular models; via paired iPhone otherwise)
Smartphone music control
Yes
Yes
On-board music storage
Yes
Yes
Voice assistant
Siri
Siri AI powered by Apple Intelligence
6. Navigation & safety Apple Watch Ultra 4
Fact
Apple Watch Ultra 2
Apple Watch Ultra 4
Maps
Yes (Apple Maps)
Yes
Offline maps
Yes (synced from iPhone)
Yes
Navigation
Yes (Apple Maps turn-by-turn)
Yes
Emergency SOS
Yes
Yes
Satellite SOS
No
Yes
Fall detection
Yes
Yes
LED flashlight
No
No
Diving
Yes (recreational scuba to 40 m with compatible app)
Yes