Amazfit T-Rex Ultra vs Garmin Forerunner 265
The Verdict
Both smartwatches target serious athletes at virtually identical price points, but excel in different areas. Amazfit T-Rex Ultra emphasizes durability with its stainless steel bezel and superior 10 ATM water resistance (certified for 45m free-diving versus Forerunner's 5 ATM), plus exceptional 20-day battery life and larger AMOLED display. Garmin Forerunner 265 counters with significantly lighter weight (47g vs 89g), better everyday wearability, and practical connectivity features including NFC and Wi-Fi that the Amazfit lacks. Both offer identical health monitoring (SpO2, heart rate, sleep tracking) and GPS capabilities. For endurance athletes prioritizing battery longevity and rugged construction, T-Rex Ultra wins. Those wanting a refined, feature-rich training companion that doesn't fatigue the wrist should choose Forerunner 265. Garmin edges out with superior software ecosystem and daily-use practicality.
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 265 if…
- →Vibrant AMOLED display is a massive upgrade over the 255's MIP screen
- →Training Readiness and Morning Report provide actionable fitness insights
- →Multi-band GPS delivers extremely accurate pace and distance 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 265
Pros
- Vibrant AMOLED display is a massive upgrade over the 255's MIP screen
- Training Readiness and Morning Report provide actionable fitness insights
- Multi-band GPS delivers extremely accurate pace and distance tracking
- 13-day battery with AMOLED is exceptional — best in its class
- Race Widget helps plan pacing strategy for upcoming events
Cons
- No built-in maps — only breadcrumb trail navigation
- No music storage on the base model (265 Music has it)
- No cellular connectivity — phone required for notifications
- Proprietary charging cable is easy to forget when traveling
Full Specifications
| Spec | Amazfit T-Rex Ultra | Garmin Forerunner 265 |
|---|---|---|
| Software | Zepp OS 2.0 | Garmin OS (Connect IQ) |
| Body | ||
| Weight | 89 g | 47 g |
| Case material | Stainless steel bezel, fiber-reinforced polymer case | Fiber-reinforced polymer |
| Water resistance | 10 ATM, ISO 22810 certified for free-diving to 45m | 5ATM |
| Health & Sensors | ||
| ECG | ||
| SpO₂ | ||
| Skin temperature | ||
| Heart rate | ||
| Sleep tracking | ||
| Battery | ||
| Battery life | Up to 20 days typical use, 80 hours GPS | Up to 13 days (smartwatch), 20 hrs GPS |
| Display | ||
| Size | 1.39 inch | 46mm (1.3 inches) |
| Type | AMOLED | AMOLED |
| Always-on display | ||
| Resolution | 454 x 454 | 416 x 416 |
| Connectivity | ||
| GPS | ||
| NFC | ||
| Wi-Fi | ||
| Cellular | ||
| Bluetooth | 5.0 | 5.0 |
| Processor | ||
| Chipset | — | Garmin custom processor |
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 265.