Amazfit T-Rex Ultra vs Fitbit Sense 2
Side-by-side specifications, scores and verdict.
Quick Verdict
Both smartwatches excel in health tracking but serve different priorities. Amazfit T-Rex Ultra dominates battery life with an impressive 20-day runtime and 80 hours of GPS logging, plus superior durability featuring a 10 ATM rating suitable for free-diving to 45m. Its 1.39-inch AMOLED display delivers sharper visuals at 454x454 resolution. Fitbit Sense 2 compensates with advanced health metrics including ECG, skin temperature monitoring, and EDA stress detection—features absent on the T-Rex. It's significantly lighter at 37.6g versus 89g, includes NFC for contactless payments, and costs $150 less. Battery life trails considerably at 6 days standard use. Choose the T-Rex Ultra if expedition-grade durability and extended battery matter most; select Fitbit Sense 2 for comprehensive health insights and everyday portability.
Full Specifications
| Specification | Amazfit T-Rex Ultra | Fitbit Sense 2 |
|---|---|---|
| Software | Zepp OS 2.0 | Fitbit OS |
| Body | ||
| Weight | 89 g | 37.6 g |
| Case material | Stainless steel bezel, fiber-reinforced polymer case | Aluminum case |
| Water resistance | 10 ATM, ISO 22810 certified for free-diving to 45m | 5 ATM |
| Health & Sensors | ||
| ECG | ||
| SpO₂ | ||
| Skin temperature | ||
| Heart rate | ||
| Sleep tracking | ||
| Battery | ||
| Battery life | Up to 20 days typical use, 80 hours GPS | Up to 6 days, 12 hours with GPS |
| Display | ||
| Size | 1.39 inch | 1.58 inch |
| Type | AMOLED | AMOLED |
| Always-on display | ||
| Resolution | 454 x 454 | 336 x 336 |
| Connectivity | ||
| GPS | ||
| NFC | ||
| Wi-Fi | ||
| Cellular | ||
| Bluetooth | 5.0 | 5.0 |
Category Scores
Pros & Cons
Amazfit T-Rex Ultra
Pros
- Excellent 20-day battery life with always-on display
- Dual-band six-satellite GPS for high accuracy
- Rugged design with 15 military-grade certifications
- Free-diving rated to 45 meters
- Offline maps with route import support
Cons
- No ECG, skin temperature, or NFC payments
- No Wi-Fi or cellular connectivity
- Zepp OS app ecosystem is limited
- Heavier than most smartwatches at 89g
- No third-party app store
Fitbit Sense 2
Pros
- Continuous EDA sensor for all-day stress tracking
- ECG and skin temperature tracking
- Lightweight and comfortable for 24/7 wear
- Up to 6 days of battery life
- Built-in GPS with Google Maps and Wallet support
Cons
- Removed third-party apps and music storage from original Sense
- No Wi-Fi connectivity
- Requires Fitbit Premium for advanced insights
- Limited smartwatch functionality compared to Wear OS
- Single physical button, no rotating crown
Related Comparisons
Explore more in smartwatches, see all Amazfit products or all Fitbit products. View full details for the Amazfit T-Rex Ultra or the Fitbit Sense 2.