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2026 comparison
Updated Jan 7, 2026
|Sources: Amazon, ManufacturerAmazfit T-Rex 3 vs OnePlus Watch 2
When it comes to the Amazfit T-Rex 3 versus the OnePlus Watch 2, the standout feature is the battery life. The Amazfit T-Rex 3 boasts an impressive 27 days on a single charge, while the OnePlus Watch 2 offers up to 100 hours. That's a significant difference for anyone prioritizing longevity in their smartwatch. In real-world use, the T-Rex 3's 1.5" AMOLED display at 2000 nits shines brightly outdoors, making it easy to read even in direct sunlight. However, if you're after a premium build, the OnePlus Watch 2's stainless steel chassis and sapphire crystal finish offer a more refined look, albeit with a smaller screen at 1.43" and lower brightness. It's all about what features matter most to you.
⚖️ Weight: 2.41 oz vs 1.73 oz🔋 Battery: 27 days vs 100 hours📱 Display: 1.5" (2000 nits) vs 1.43" (600 nits)
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Amazfit T-Rex 3
★4.5
(1,926)•Amazon
Compatibility:Android 7.0 or later; iOS 14.0 or later (Zepp App required)
Operating System:Zepp OS 4
Case Size:48.5mm x 48.5mm x 13.75mm
Case Material:Polymer middle frame; Stainless steel bezel (316L)
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OnePlus Watch 2
★4.6
(538)•Amazon
Compatibility:Android 8.0+ only (requires GMS 23.45.23+); iOS and Android Go edition NOT supported
Operating System:Wear OS 4 + RTOS (Dual-Engine Architecture)
Case Size:47mm (47.0 x 46.6 x 12.1 mm / 1.85 x 1.83 x 0.47 in)
Case Material:Chassis: Stainless steel; Bottom: Plastic (PC/PC+glass fiber); Cover: 2.5D Sapphire Crystal
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Key spec differences
Only the specs that differ are shown here. Winners are highlighted when the data is clear.
Winner= clear advantage
Spec
Amazfit T-Rex 3
OnePlus Watch 2
Display2 specs
Display SizeKey
Amazfit T-Rex 3
1.5 in (38.1 mm) diameter
OnePlus Watch 2
1.43 in (3.63 cm)
Resolution
Amazfit T-Rex 3
480 x 480 pixels (322 ppi)
OnePlus Watch 2
466 x 466 pixels (326 ppi); 600 nits default brightness
Performance1 specs
Storage
Amazfit T-Rex 3
32GB (Approx. 26GB user-accessible for Music/Maps)
OnePlus Watch 2
32 GB ROM + 2 GB RAM (Approx. 4GB reserved for RTOS)
Battery1 specs
Battery CapacityKey
Amazfit T-Rex 3
700 mAh; Up to 27 days (Typical usage); Up to 13 days (Heavy usage); Up to 42 hours (Accuracy GPS mode); Up to 114 hours (GPS Long Battery Life)
OnePlus Watch 2
500 mAh; Up to 100 hours (Smart Mode); Up to 48 hours (Heavy Use); Up to 12 days (Power Saver Mode)
Design2 specs
Weight
Amazfit T-Rex 3
68.3 g (without strap)
OnePlus Watch 2
49 g (Watch only) / 80 g (with Fluororubber strap)Winner
Water Resistance
Amazfit T-Rex 3
10 ATM (100 meters); Freediving certified (EN13319) to 45m
OnePlus Watch 2
5 ATM (50 m) + IP68 (1.5m for 30 min)
Software1 specs
Operating System
Amazfit T-Rex 3
Zepp OS 4
OnePlus Watch 2
Wear OS 4 + RTOS (Dual-Engine Architecture)
Connectivity1 specs
Connectivity
Amazfit T-Rex 3
Wi-Fi (2.4GHz); Bluetooth 5.2; BLE
OnePlus Watch 2
Bluetooth 5.0, Wi-Fi 2.4GHz/5GHz (802.11 a/b/g/n)
+Full specs, pros, and cons
Everything side-by-side with ratings and the full spec list.
Expand
Full specs, pros, and cons
Everything side-by-side with ratings and the full spec list.
Comparison: Amazfit T-Rex 3 vs OnePlus Watch 2
Amazfit T-Rex 3
★4.5(1,926)Amazon
OnePlus Watch 2
★4.6(538)Amazon
| Criterion | Amazfit T-Rex 3 | OnePlus Watch 2 |
|---|---|---|
| Rating | ★4.5(1,926)Amazon | ★4.6(538)Amazon |
Compatibility | Android 7.0 or later; iOS 14.0 or later (Zepp App required) | Android 8.0+ only (requires GMS 23.45.23+); iOS and Android Go edition NOT supported |
Operating System | Zepp OS 4 | Wear OS 4 + RTOS (Dual-Engine Architecture) |
Case Size | 48.5mm x 48.5mm x 13.75mm | 47mm (47.0 x 46.6 x 12.1 mm / 1.85 x 1.83 x 0.47 in) |
Case Material | Polymer middle frame; Stainless steel bezel (316L) | Chassis: Stainless steel; Bottom: Plastic (PC/PC+glass fiber); Cover: 2.5D Sapphire Crystal |
Display Type | AMOLED; Gorilla Glass; Peak brightness 2000 nits | AMOLED touchscreen |
Display Size | 1.5 in (38.1 mm) diameter | 1.43 in (3.63 cm) |
Resolution | 480 x 480 pixels (322 ppi) | 466 x 466 pixels (326 ppi); 600 nits default brightness |
Always On Display | Yes | Yes |
Water Resistance | 10 ATM (100 meters); Freediving certified (EN13319) to 45m | 5 ATM (50 m) + IP68 (1.5m for 30 min) |
Durability | MIL-STD-810H (70°C heat / -30°C cold / Shock / Humidity); Mud-resistant bridge and buttons | MIL-STD-810H certified; Sapphire crystal face; Operating temp: -20°C to 55°C |
GPS | Dual-band GNSS (L1+L5); 6 Satellite Positioning Systems (GPS, GLONASS, Galileo, BeiDou, QZSS, NAVIC) | Dual-frequency L1 + L5; Beidou, GPS, Galileo, GLONASS, QZSS |
Connectivity | Wi-Fi (2.4GHz); Bluetooth 5.2; BLE | Bluetooth 5.0, Wi-Fi 2.4GHz/5GHz (802.11 a/b/g/n) |
NFC Payments | Zepp Pay (Europe/parts of Asia only); Not supported on US models | Yes (Google Wallet) |
Sensors | BioTracker™ 6.0 PPG biometric sensor (SpO2, Heart Rate); Accelerometer; Gyroscope; Geomagnetic sensor; Barometric altimeter; Ambient light sensor; Temperature sensor (skin/water) | Optical heart rate; optical pulse oximeter (SpO2); accelerometer; gyroscope; geomagnetic sensor; light sensor; barometer |
Health Features | Readiness Score; HRV (Heart Rate Variability); Sleep Breathing Quality; One-tap measuring (HR, SpO2, Stress, Breathing rate); Sleep stages (REM/Deep/Light); PAI Health Assessment | Sleep tracking (stages, score, snoring risk); OHealth breathing training; stress monitoring; heart rate (high/low alerts, resting); blood oxygen (SpO2) |
Workout Modes | Hyrox Race mode; Ultramarathon; Freediving; Strength Training (auto-detection of 25 movements); Triathlon; Skiing; Snowboarding; Surf; and 170+ others | 100+ sports modes; 6 auto-detection modes (running, walking, cycling, swimming, rowing, elliptical); professional analysis for running, tennis, skiing |
Storage | 32GB (Approx. 26GB user-accessible for Music/Maps) | 32 GB ROM + 2 GB RAM (Approx. 4GB reserved for RTOS) |
Speaker Mic | Microphone (for Zepp Flow voice commands); No Speaker (Buzzer/Beeper only for alerts) | Yes (Built-in speaker and microphone) |
Calls | No (Cannot answer calls on wrist; can reject/ignore calls) | Yes (Bluetooth calling supported in Smart and Power Saver modes) |
Battery | 700 mAh; Up to 27 days (Typical usage); Up to 13 days (Heavy usage); Up to 42 hours (Accuracy GPS mode); Up to 114 hours (GPS Long Battery Life) | 500 mAh; Up to 100 hours (Smart Mode); Up to 48 hours (Heavy Use); Up to 12 days (Power Saver Mode) |
Charging | Magnetic charging base (2-pin); Approx. 3 hours to full charge | VOOC Fast Charging (7.5W); 100% in 60 mins; 1 day power in 10 mins |
Weight | 68.3 g (without strap) | 49 g (Watch only) / 80 g (with Fluororubber strap) |
Band Sizes | 22mm width; Fits 145–210mm wrists (Proprietary screws but includes adapters for standard bands in some regions) | Fits wrist sizes 140–210 mm; standard 22 mm quick-release width |
Extras | Offline Maps (Contour/Terrain); Turn-by-turn navigation; Zepp Flow (AI voice assistant); Night Display mode; Glove mode | Dual-Engine architecture (Snapdragon W5 + BES2700); Google Play Store; Google Maps; Google Assistant; Flashlight; Compass; Media controls |
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Amazfit T-Rex 3
Rating:★4.5(1,926)Amazon
Compatibility:Android 7.0 or later; iOS 14.0 or later (Zepp App required)
Operating System:Zepp OS 4
Case Size:48.5mm x 48.5mm x 13.75mm
Case Material:Polymer middle frame; Stainless steel bezel (316L)
Display Type:AMOLED; Gorilla Glass; Peak brightness 2000 nits
Display Size:1.5 in (38.1 mm) diameter
Resolution:480 x 480 pixels (322 ppi)
Always On Display:Yes
Water Resistance:10 ATM (100 meters); Freediving certified (EN13319) to 45m
Durability:MIL-STD-810H (70°C heat / -30°C cold / Shock / Humidity); Mud-resistant bridge and buttons
GPS:Dual-band GNSS (L1+L5); 6 Satellite Positioning Systems (GPS, GLONASS, Galileo, BeiDou, QZSS, NAVIC)
Connectivity:Wi-Fi (2.4GHz); Bluetooth 5.2; BLE
NFC Payments:Zepp Pay (Europe/parts of Asia only); Not supported on US models
Sensors:BioTracker™ 6.0 PPG biometric sensor (SpO2, Heart Rate); Accelerometer; Gyroscope; Geomagnetic sensor; Barometric altimeter; Ambient light sensor; Temperature sensor (skin/water)
Health Features:Readiness Score; HRV (Heart Rate Variability); Sleep Breathing Quality; One-tap measuring (HR, SpO2, Stress, Breathing rate); Sleep stages (REM/Deep/Light); PAI Health Assessment
Workout Modes:Hyrox Race mode; Ultramarathon; Freediving; Strength Training (auto-detection of 25 movements); Triathlon; Skiing; Snowboarding; Surf; and 170+ others
Storage:32GB (Approx. 26GB user-accessible for Music/Maps)
Speaker Mic:Microphone (for Zepp Flow voice commands); No Speaker (Buzzer/Beeper only for alerts)
Calls:No (Cannot answer calls on wrist; can reject/ignore calls)
Battery:700 mAh; Up to 27 days (Typical usage); Up to 13 days (Heavy usage); Up to 42 hours (Accuracy GPS mode); Up to 114 hours (GPS Long Battery Life)
Charging:Magnetic charging base (2-pin); Approx. 3 hours to full charge
Weight:68.3 g (without strap)
Band Sizes:22mm width; Fits 145–210mm wrists (Proprietary screws but includes adapters for standard bands in some regions)
Extras:Offline Maps (Contour/Terrain); Turn-by-turn navigation; Zepp Flow (AI voice assistant); Night Display mode; Glove mode
✓ Pros:
- • Incredible 27-day battery life crushes the competition
- • Large, bright 1.5" AMOLED (2000 nits) is easy to read outdoors
- • Free offline contour maps with turn-by-turn navigation
- • Freediving certified to 45m (rare at this price point)
- • Generous 32GB storage for offline music and global maps
✗ Cons:
- • No built-in speaker (alerts are beeps/vibrations only)
- • NFC payments (Zepp Pay) are not supported on US hardware
- • Large 48.5mm case is bulky for smaller wrists
- • Proprietary strap system requires adapters to use standard bands
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OnePlus Watch 2
Rating:★4.6(538)Amazon
Compatibility:Android 8.0+ only (requires GMS 23.45.23+); iOS and Android Go edition NOT supported
Operating System:Wear OS 4 + RTOS (Dual-Engine Architecture)
Case Size:47mm (47.0 x 46.6 x 12.1 mm / 1.85 x 1.83 x 0.47 in)
Case Material:Chassis: Stainless steel; Bottom: Plastic (PC/PC+glass fiber); Cover: 2.5D Sapphire Crystal
Display Type:AMOLED touchscreen
Display Size:1.43 in (3.63 cm)
Resolution:466 x 466 pixels (326 ppi); 600 nits default brightness
Always On Display:Yes
Water Resistance:5 ATM (50 m) + IP68 (1.5m for 30 min)
Durability:MIL-STD-810H certified; Sapphire crystal face; Operating temp: -20°C to 55°C
GPS:Dual-frequency L1 + L5; Beidou, GPS, Galileo, GLONASS, QZSS
Connectivity:Bluetooth 5.0, Wi-Fi 2.4GHz/5GHz (802.11 a/b/g/n)
NFC Payments:Yes (Google Wallet)
Sensors:Optical heart rate; optical pulse oximeter (SpO2); accelerometer; gyroscope; geomagnetic sensor; light sensor; barometer
Health Features:Sleep tracking (stages, score, snoring risk); OHealth breathing training; stress monitoring; heart rate (high/low alerts, resting); blood oxygen (SpO2)
Workout Modes:100+ sports modes; 6 auto-detection modes (running, walking, cycling, swimming, rowing, elliptical); professional analysis for running, tennis, skiing
Storage:32 GB ROM + 2 GB RAM (Approx. 4GB reserved for RTOS)
Speaker Mic:Yes (Built-in speaker and microphone)
Calls:Yes (Bluetooth calling supported in Smart and Power Saver modes)
Battery:500 mAh; Up to 100 hours (Smart Mode); Up to 48 hours (Heavy Use); Up to 12 days (Power Saver Mode)
Charging:VOOC Fast Charging (7.5W); 100% in 60 mins; 1 day power in 10 mins
Weight:49 g (Watch only) / 80 g (with Fluororubber strap)
Band Sizes:Fits wrist sizes 140–210 mm; standard 22 mm quick-release width
Extras:Dual-Engine architecture (Snapdragon W5 + BES2700); Google Play Store; Google Maps; Google Assistant; Flashlight; Compass; Media controls
✓ Pros:
- • Groundbreaking 100-hour battery life for a full-featured Wear OS watch
- • Premium build with stainless steel chassis and sapphire crystal standard
- • Dual-frequency GPS (L1+L5) ensures high accuracy in urban environments
- • Fast charging provides a full day's power in just 10 minutes
- • Fluid performance via Snapdragon W5 Gen 1 processor
✗ Cons:
- • Available in only one large size (47mm), which may not fit small wrists
- • No LTE/Cellular option available
- • Strictly incompatible with iOS (iPhone)
- • Crown rotates but does not function for scrolling menus
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Check Price on Amazon→
Which one is better?
The Amazfit T-Rex 3 is the better buy for most people - its 27-day battery life crushes the OnePlus Watch 2's 100 hours. That said, grab the OnePlus Watch 2 if you want a premium feel and don't mind the shorter battery life - it's lighter at 1.73 oz compared to the T-Rex's 2.41 oz.
Who should buy each?
Choose the Amazfit T-Rex 3 if: you need up to 27 days of battery life, enjoy outdoor activities with its rugged design, or want a larger, brighter display.
Choose the OnePlus Watch 2 if: you appreciate a premium build with stainless steel, want a smartwatch that supports Bluetooth calling, or need a watch that charges quickly. (1.73 oz weight)
Conclusion
With the key differences outlined, the decision should be clearer. Both options deliver quality—choose the one that fits your priorities.
Frequently Asked Questions
+Which has better value?
Amazfit T-Rex 3 excels if you value incredible 27-day battery life crushes the competition. OnePlus Watch 2 is better if you prioritize groundbreaking 100-hour battery life for a full-featured wear os watch. Pick based on your budget and daily use.
+Is this an independent review?
Yes. We use affiliate links for monetization, but recommendations are research-driven and unbiased.
+Do newer models exist?
Check release timelines from the manufacturers and compare pricing before you buy. We refresh this page when major updates land.
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