Amazfit T-Rex 2 vs Fitbit Versa 4
The Verdict
Amazfit T-Rex 2 and Fitbit Versa 4 target different priorities. The T-Rex 2 dominates battery life with up to 24 days of typical use and 45 hours of continuous GPS tracking, making it ideal for outdoor enthusiasts and those avoiding frequent charging. Its 47mm AMOLED display with 454x454 resolution offers a larger, sharper screen, while the fiber-reinforced polymer construction with metal buttons provides ruggedness for sports and adventure. However, the Versa 4 packs more health sensors including ECG, skin temperature monitoring, and SpO2 tracking alongside superior connectivity with NFC for contactless payments and WiFi support. Weighing just 37.6g compared to the T-Rex 2's 66.5g, the Versa 4 feels considerably lighter and more refined for daily wear. Battery life is its main weakness at 6 days versus 24, though still respectable. The Fitbit ecosystem remains more mature for fitness tracking and integration with Google services. Choose the T-Rex 2 if you prioritize durability, battery longevity, and GPS performance; select the Versa 4 if you value health sensors, payments, and everyday wearability with excellent fitness features.
Who Should Buy
Buy the Amazfit T-Rex 2 if…
- →MIL-STD-810G rated for extreme temperature, humidity, and shock resistance
- →24-day battery life with 45 hours of continuous GPS tracking
- →10ATM water resistance for swimming and water sports
Buy the Fitbit Versa 4 if…
- →Best sleep tracking of any smartwatch — Daily Readiness Score
- →ECG, SpO2, and skin temperature at $179 is strong value
- →6-day battery life — charge once a week
Category Scores
Pros & Cons
Amazfit T-Rex 2
Pros
- MIL-STD-810G rated for extreme temperature, humidity, and shock resistance
- 24-day battery life with 45 hours of continuous GPS tracking
- 10ATM water resistance for swimming and water sports
- Dual-band GPS for accurate outdoor positioning
- AMOLED display is vibrant and readable in sunlight
Cons
- 66.5 g is heavy — can be uncomfortable for sleep tracking
- No NFC or cellular connectivity
- Zepp OS has limited smart features and app support
- No ECG monitoring
- Bulky design may not suit formal or everyday casual wear
Fitbit Versa 4
Pros
- Best sleep tracking of any smartwatch — Daily Readiness Score
- ECG, SpO2, and skin temperature at $179 is strong value
- 6-day battery life — charge once a week
- NFC for Google Wallet contactless payments
- Google integration with Maps, Wallet, and YouTube Music
Cons
- Fitbit OS is being sunset — unclear future app support
- GPS accuracy is less reliable than Garmin or Apple Watch
- Limited third-party app ecosystem
- Physical button replaced with a haptic side button — divisive
Full Specifications
| Spec | Amazfit T-Rex 2 | Fitbit Versa 4 |
|---|---|---|
| Software | Zepp OS | Fitbit OS (transitioning to Wear OS) |
| Body | ||
| Weight | 66.5 g (without strap) | 37.6 g |
| Case material | Fiber-reinforced polymer with metal buttons | Aluminum |
| Water resistance | 10ATM | WR50 |
| Health & Sensors | ||
| ECG | ||
| SpO₂ | ||
| Skin temperature | ||
| Heart rate | ||
| Sleep tracking | ||
| Battery | ||
| Battery life | Up to 24 days (typical), 45 hrs GPS | Up to 6 days (typical usage) |
| Display | ||
| Size | 47mm | 40 mm (1.58 inches) |
| Type | AMOLED Always-On | AMOLED |
| Always-on display | ||
| Resolution | 454 x 454 | 336 x 336 |
| Processor | ||
| Chipset | Huami custom SoC | Fitbit proprietary |
| Connectivity | ||
| GPS | ||
| NFC | ||
| Wi-Fi | ||
| Cellular | ||
| Bluetooth | 5.0 | 5.0 |
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This comparison is based on verified manufacturer specifications covering display, performance, camera, battery, and build quality. Scores are generated by analyzing specs across weighted categories on a 10-point scale. Learn more about our methodology.
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