Between the T-Rex 3 and Pixel Watch 3 (45mm), the T-Rex 3 comes out ahead in battery life and display size, while the Pixel Watch 3 (45mm) wins on weight and ecg. Overall, the T-Rex 3 scores 79.7 and the Pixel Watch 3 (45mm) scores 46.7 on our Mars Score.
Which should you buy?
The T-Rex 3 is the clear pick on raw spec strength, leading by 33.0 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
Pick the T-Rex 3 if your top frustration with your current device is running out of charge before the day ends — endurance is the lead spec here. The biggest gaps in its favor are battery life, display size, water resistance.
Pick the Pixel Watch 3 (45mm) if you carry the device everywhere and weight or thickness has been the deciding factor before. Its strongest claims are weight, ecg, cellular.
Both ship with comparable spo2, peak brightness, so those specs don't separate the two — focus on the differences below.
Bottom line: the T-Rex 3 is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Amazfit - T-Rex 3 wins
- ▲Battery life — 1766.67% more. 672 h vs 36 h.
- ▲Display size — 7.14% more. 1.5 " vs 1.4 ".
- ▲Water resistance — 5.00 ATM more. 10 vs 5.
Why Google - Pixel Watch 3 (45mm) wins
- ▲Weight — 31.00 g less. 37 vs 68.
- ▲Has ECG.
- ▲Has Cellular.
Spec comparison
Design
| Spec | Amazfit - T-Rex 3 | Google - Pixel Watch 3 (45mm) |
|---|---|---|
| Case size | 48.5 mmlead | 45 mm |
| Weight | 68 g | 37 glead |
| Case material | polymer | aluminum |
| Water resistanceⓘ | 10 ATMlead | 5 ATM |
Display
| Spec | Amazfit - T-Rex 3 | Google - Pixel Watch 3 (45mm) |
|---|---|---|
| Display size | 1.5 "lead | 1.4 " |
| Always-on display | true | true |
| Peak brightnessⓘ | 2000 nits | 2000 nits |
Health & Fitness
| Spec | Amazfit - T-Rex 3 | Google - Pixel Watch 3 (45mm) |
|---|---|---|
| ECG | false | truelead |
| SpO2 | true | true |
| Temperature sensor | true | true |
| Sleep tracking | true | true |
| Blood pressure | false | false |
Battery & Connectivity
| Spec | Amazfit - T-Rex 3 | Google - Pixel Watch 3 (45mm) |
|---|---|---|
| Battery life | 672 hlead | 36 h |
| GPS | true | true |
| Cellular | false | truelead |
| NFC | false | truelead |
| OS | Zepp OSlead | WearOS |
Frequently asked
Which has longer battery life, T-Rex 3 or Pixel Watch 3 (45mm)?+
T-Rex 3 lasts 672h vs 36h.
Do T-Rex 3 or Pixel Watch 3 (45mm) support ECG?+
Pixel Watch 3 (45mm) supports ECG; T-Rex 3 does not.
Which has cellular, T-Rex 3 or Pixel Watch 3 (45mm)?+
Pixel Watch 3 (45mm) offers a cellular variant; T-Rex 3 is Wi-Fi only.
Spec-level deep dives
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