Between the T-Rex 3 and Vantage V3, the T-Rex 3 comes out ahead in battery life and peak brightness, while the Vantage V3 wins on weight and ecg. Overall, the T-Rex 3 scores 79.7 and the Vantage V3 scores 53.5 on our Mars Score.
Which should you buy?
The T-Rex 3 is the clear pick on raw spec strength, leading by 26.2 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, peak brightness, display size, among others.
Pick the Vantage V3 if you carry the device everywhere and weight or thickness has been the deciding factor before. Its strongest claims are weight, ecg.
Both ship with comparable cellular, spo2, 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 — 300.00% more. 672 h vs 168 h.
- ▲Peak brightness — 100.00% more. 2000 nits vs 1000 nits.
- ▲Display size — 7.91% more. 1.5 " vs 1.39 ".
- ▲Water resistance — 5.00 ATM more. 10 vs 5.
Why Polar - Vantage V3 wins
- ▲Weight — 11.00 g less. 57 vs 68.
- ▲Has ECG.
Spec comparison
Design
| Spec | Amazfit - T-Rex 3 | Polar - Vantage V3 |
|---|---|---|
| Case size | 48.5 mmlead | 47 mm |
| Weight | 68 g | 57 glead |
| Case material | polymer | aluminum |
| Water resistanceⓘ | 10 ATMlead | 5 ATM |
Display
| Spec | Amazfit - T-Rex 3 | Polar - Vantage V3 |
|---|---|---|
| Display size | 1.5 "lead | 1.39 " |
| Always-on display | true | true |
| Peak brightnessⓘ | 2000 nitslead | 1000 nits |
Health & Fitness
| Spec | Amazfit - T-Rex 3 | Polar - Vantage V3 |
|---|---|---|
| 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 | Polar - Vantage V3 |
|---|---|---|
| Battery life | 672 hlead | 168 h |
| GPS | true | true |
| Cellular | false | false |
| NFC | false | false |
| OS | Zepp OSlead | Polar OS |
Frequently asked
Which has longer battery life, T-Rex 3 or Vantage V3?+
T-Rex 3 lasts 672h vs 168h.
Do T-Rex 3 or Vantage V3 support ECG?+
Vantage V3 supports ECG; T-Rex 3 does not.
Which has cellular, T-Rex 3 or Vantage V3?+
Neither offers cellular.
Spec-level deep dives
More from the same brands
vsMars is reader-supported. When you buy through links on our site, we may earn an affiliate commission at no extra cost to you. Learn more.