Between the OnePlus Watch 3 and Vantage V3, the OnePlus Watch 3 comes out ahead in peak brightness and display size, while the Vantage V3 wins on battery life and weight. Overall, the OnePlus Watch 3 scores 53.9 and the Vantage V3 scores 53.5 on our Mars Score.
Which should you buy?
These two are nearly even on the Mars Score (53.9 vs 53.5). The decision isn't about overall quality — both clear the bar — it's about which specific trade-offs fit your use.
Pick the OnePlus Watch 3 if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. The biggest gaps in its favor are peak brightness, display size.
Pick the Vantage V3 if your top frustration with your current device is running out of charge before the day ends — endurance is the lead spec here. Its strongest claims are battery life, weight.
Both ship with comparable ecg, cellular, spo2, so those specs don't separate the two — focus on the differences below.
Bottom line: there is no wrong answer here — match the spec advantages to how you actually use the product. The Mars Score parity tells you both are well-rounded; the differences are about trade-offs, not quality.
Why OnePlus Watch 3 wins
- ▲Peak brightness — 120.00% more. 2200 nits vs 1000 nits.
- ▲Display size — 7.91% more. 1.5 " vs 1.39 ".
Why Polar - Vantage V3 wins
- ▲Battery life — 40.00% more. 168 h vs 120 h.
- ▲Weight — 24.00 g less. 57 vs 81.
Spec comparison
Design
| Spec | OnePlus Watch 3 | Polar - Vantage V3 |
|---|---|---|
| Case size | 46.5 mm | 47 mmlead |
| Weight | 81 g | 57 glead |
| Case material | stainless steel | aluminum |
| Water resistanceⓘ | 5 ATM | 5 ATM |
Display
| Spec | OnePlus Watch 3 | Polar - Vantage V3 |
|---|---|---|
| Display size | 1.5 "lead | 1.39 " |
| Always-on display | true | true |
| Peak brightnessⓘ | 2200 nitslead | 1000 nits |
Health & Fitness
| Spec | OnePlus Watch 3 | Polar - Vantage V3 |
|---|---|---|
| ECG | true | true |
| SpO2 | true | true |
| Temperature sensor | true | true |
| Sleep tracking | true | true |
| Blood pressure | false | false |
Battery & Connectivity
| Spec | OnePlus Watch 3 | Polar - Vantage V3 |
|---|---|---|
| Battery life | 120 h | 168 hlead |
| GPS | true | true |
| Cellular | false | false |
| NFC | truelead | false |
| OS | WearOS | Polar OSlead |
Frequently asked
Which has longer battery life, OnePlus Watch 3 or Vantage V3?+
Vantage V3 lasts 168h vs 120h.
Do OnePlus Watch 3 or Vantage V3 support ECG?+
Both support ECG.
Which has cellular, OnePlus Watch 3 or Vantage V3?+
Neither offers cellular.
Spec-level deep dives
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