Samsung Galaxy Watch 9 vs OnePlus Watch 4 specs comparison
Galaxy Watch 9 is the better fit if you want a smaller watch and Samsung’s extensive health ecosystem. OnePlus Watch 4 is more compelling if battery life and a larger titanium build matter more.
At a glance
What's different?
The strongest database-backed differences, without pretending every different number is an advantage.
Samsung Galaxy Watch 9
- Phone compatibility Android with Google Mobile Services
- Blood pressure measurement Yes (Samsung Health Monitor; availability varies by market, calibration required)
- Cellular connectivity Not available on the other model
- Body composition Not available on the other model
- 21% lighter 34.0 g vs 43 g
OnePlus Watch 4
- Phone compatibility Android 9.0+ with GMS 23.45.23+; no iOS or Android Go support
- Much longer battery life 5 days vs 40 hours
Both include ECG, blood oxygen tracking, skin temperature tracking, HRV tracking, on-board music, Bluetooth calling, a microphone.
Full comparison
The full record
78 specifications across 6 areas, with 28 genuine differences.
1. Design & display Mixed
Fact
Samsung Galaxy Watch 9
OnePlus Watch 4
Release date
2026-07
2026-04-28
Physical size
44 mm: 46.0 x 43.7 x 8.6 mm; 40 mm: 42.7 x 40.4 x 8.6 mm
47.4 x 47.4 x 11.0 mm
Weight
44 mm: 34.0 g; 40 mm: 31.5 g
43 g without strap; 68 g with strap
Material
Armor Aluminum case; sapphire crystal
Titanium alloy case, PA with fiberglass bottom case, sapphire crystal, fluororubber strap
Water resistance
5 ATM; IP68; MIL-STD-810H
5 ATM; IP68; IP69; MIL-STD-810H
Color options
Graphite, Silver, Cream
Midnight Titanium, Evergreen Titanium
Display type
Super AMOLED, full-colour Always On Display
LTPO OLED
Display size
44 mm: 1.47 inch (37.3 mm); 40 mm: 1.34 inch (34 mm)
1.5 inch
Display resolution
44 mm: 480 x 480 pixels; 40 mm: 438 x 438 pixels
466 x 466 pixels, 310 ppi
Display brightness
Up to 3,000 nits
Up to 3,000 nits
Display protection
Sapphire crystal
Sapphire crystal
2. Battery & charging OnePlus Watch 4
Fact
Samsung Galaxy Watch 9
OnePlus Watch 4
Battery
Rechargeable battery; 44 mm: 445 mAh; 40 mm: 390 mAh
Rechargeable battery; 646 mAh typical (632 mAh rated)
Battery life
Up to 40 hours with AOD off; up to 30 hours with AOD on
Up to 5 days smart mode, 3 days heavy use, 16 days power saver
Charging
Fast wireless charging
Charging base with USB-C cable
3. Sensors & positioning No clear edge
Fact
Samsung Galaxy Watch 9
OnePlus Watch 4
GNSS type
Built-in dual-band GNSS
Built-in dual-band GNSS
GPS
Yes
Yes
GALILEO
Yes
Yes
GLONASS
Yes
Yes
QZSS
Yes
Yes
Beidou
Yes
Yes
Accelerometer
Yes
Yes
Gyroscope
Yes
Yes
Barometric altimeter
Yes
Yes
Compass
Yes
Yes
Geomagnetic
Yes
Yes
Ambient light sensor
Yes
Yes
Optical heart rate
Yes
Yes
Electrical heart rate
Yes
Yes
SpO2
Yes
Yes
Temperature
Yes
Yes
Galvanic skin response
Yes
No
Microphone
Yes
Yes
Speakers
Yes
Yes
Vibration motor
Yes
Yes
4. Health & activity Samsung Galaxy Watch 9
Fact
Samsung Galaxy Watch 9
OnePlus Watch 4
Steps
Yes
Yes
Distance
Yes
Yes
Calories burned
Yes
Yes
Floors
Yes
Yes
Sports tracking
Yes
Yes (100+ sports modes)
Sleep
Yes
Yes
Heart rate
Yes
Yes
HRV
Yes
Yes
Stress
Yes
Yes
Blood oxygen
Yes
Yes
Respiration rate
Yes
Yes
Skin temperature
Yes
Yes
ECG
Yes
Yes (regional availability)
Blood pressure
Yes (Samsung Health Monitor; availability varies by market, calibration required)
No
Body composition
Yes
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
Yes
Pulse wave arrhythmia analysis
Yes
No
5. Smart features No clear edge
Fact
Samsung Galaxy Watch 9
OnePlus Watch 4
Smartphone compatibility
Android with Google Mobile Services
Android 9.0+ with GMS 23.45.23+; no iOS or Android Go support
Operating system at launch
Wear OS 7 Powered by Samsung; One UI 9 Watch
OxygenOS Watch 8 + Wear OS 6
Processor
Qualcomm Snapdragon Wear Elite / SDW6100 (3 nm, penta-core)
Qualcomm Snapdragon W5 + BES2800
RAM
2 GB
2 GB
Storage
32 GB
32 GB
Bluetooth
Yes (6.0)
Yes (5.2)
Wi-Fi
Yes (802.11 a/b/g/n, 2.4/5 GHz)
Yes (2.4/5 GHz)
NFC / connected pay
Yes
Yes (Google Wallet)
UWB
No
No
Cellular
Optional LTE/eSIM
No
Smartphone notifications
Yes
Yes
Bluetooth calling
Yes
Yes
Smartphone music control
Yes
Yes
On-board music storage
Yes
Yes
Voice assistant
Google Gemini / Bixby
Gemini / Google Assistant
6. Navigation & safety No clear edge
Fact
Samsung Galaxy Watch 9
OnePlus Watch 4
Maps
Yes (Google Maps)
Yes (Google Maps)
Offline maps
Yes (Google Maps)
Yes (Google Maps; software-dependent)
Navigation
Yes (turn-by-turn navigation)
Yes (Google Maps)
Emergency SOS
Yes
Yes (Emergency Rescue)
Satellite SOS
No
No
Fall detection
Yes
Yes
LED flashlight
No
No