Amazfit T-Rex Ultra vs Garmin Forerunner 965
The Verdict
Both smartwatches deliver premium fitness tracking in a rugged package, but serve different priorities. Amazfit T-Rex Ultra excels with exceptional 20-day battery life and aggressive styling via stainless steel bezel, weighing 89g. Garmin Forerunner 965 counters with significantly lighter 53g construction, skin temperature monitoring, NFC payments, and WiFi connectivity,practical features the Amazfit lacks. Display quality matches identically at 1.39-1.4 inches AMOLED 454x454. Battery longevity favors Amazfit (20 vs 23 days), though Garmin's GPS endurance differs substantially (31 vs 80 hours indicates different power profiles). For serious runners prioritizing connected features and lightweight comfort, Forerunner 965 justifies its $150 premium. Outdoor adventurers valuing maximum battery and durability should lean T-Rex Ultra.
Who Should Buy
Buy the Amazfit T-Rex Ultra if…
- →Excellent 20-day battery life with always-on display
- →Dual-band six-satellite GPS for high accuracy
- →Rugged design with 15 military-grade certifications
Buy the Garmin Forerunner 965 if…
- →23-day battery life in smartwatch mode for serious endurance athletes
- →First Forerunner with AMOLED display — bright and easy to read
- →Multi-band GPS with SatIQ for highly accurate outdoor tracking
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
Garmin Forerunner 965
Pros
- 23-day battery life in smartwatch mode for serious endurance athletes
- First Forerunner with AMOLED display — bright and easy to read
- Multi-band GPS with SatIQ for highly accurate outdoor tracking
- Advanced running metrics: running power, VO2 max, race predictor
- Garmin Pay NFC and music storage for offline playback
Cons
- No ECG sensor
- No cellular connectivity
- Garmin OS app ecosystem is very limited compared to Wear OS or watchOS
- Expensive at $599 for a running-focused device
Full Specifications
| Spec | Amazfit T-Rex Ultra | Garmin Forerunner 965 |
|---|---|---|
| Software | Zepp OS 2.0 | Garmin OS |
| Body | ||
| Weight | 89 g | 53 g |
| Case material | Stainless steel bezel, fiber-reinforced polymer case | Fiber-reinforced polymer with titanium bezel |
| Water resistance | 10 ATM, ISO 22810 certified for free-diving to 45m | 10 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 23 days smartwatch mode, 31 hrs GPS |
| Display | ||
| Size | 1.39 inch | 1.4 inch |
| Type | AMOLED | AMOLED |
| Always-on display | ||
| Resolution | 454 x 454 | 454 x 454 |
| Connectivity | ||
| GPS | ||
| NFC | ||
| Wi-Fi | ||
| Cellular | ||
| Bluetooth | 5.0 | 5.0 |
| Processor | ||
| Chipset | — | Garmin proprietary |
Related Comparisons
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.
Explore more in smartwatches, see all Amazfit products or all Garmin products. View full details for the Amazfit T-Rex Ultra or the Garmin Forerunner 965.