Between the OnePlus Watch 3 and Pixel Watch 3 (45mm), the OnePlus Watch 3 comes out ahead in battery life and peak brightness, while the Pixel Watch 3 (45mm) wins on weight and cellular. Overall, the OnePlus Watch 3 scores 53.9 and the Pixel Watch 3 (45mm) scores 46.7 on our Mars Score.
Which should you buy?
The OnePlus Watch 3 edges ahead on the Mars Score (53.9 vs 46.7), but the 7.2-point gap is small enough that the right pick comes down to which spec advantages matter to you.
Pick the OnePlus Watch 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.
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, cellular.
Both ship with comparable ecg, spo2, water resistance, so those specs don't separate the two — focus on the differences below.
Bottom line: the OnePlus Watch 3 is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why OnePlus Watch 3 wins
- ▲Battery life — 233.33% more. 120 h vs 36 h.
- ▲Peak brightness — 10.00% more. 2200 nits vs 2000 nits.
- ▲Display size — 7.14% more. 1.5 " vs 1.4 ".
Why Google - Pixel Watch 3 (45mm) wins
- ▲Weight — 44.00 g less. 37 vs 81.
- ▲Has Cellular.
Spec comparison
Design
| Spec | OnePlus Watch 3 | Google - Pixel Watch 3 (45mm) |
|---|---|---|
| Case size | 46.5 mmlead | 45 mm |
| Weight | 81 g | 37 glead |
| Case material | stainless steel | aluminum |
| Water resistanceⓘ | 5 ATM | 5 ATM |
Display
| Spec | OnePlus Watch 3 | Google - Pixel Watch 3 (45mm) |
|---|---|---|
| Display size | 1.5 "lead | 1.4 " |
| Always-on display | true | true |
| Peak brightnessⓘ | 2200 nitslead | 2000 nits |
Health & Fitness
| Spec | OnePlus Watch 3 | Google - Pixel Watch 3 (45mm) |
|---|---|---|
| ECG | true | true |
| SpO2 | true | true |
| Temperature sensor | true | true |
| Sleep tracking | true | true |
| Blood pressure | false | false |
Battery & Connectivity
| Spec | OnePlus Watch 3 | Google - Pixel Watch 3 (45mm) |
|---|---|---|
| Battery life | 120 hlead | 36 h |
| GPS | true | true |
| Cellular | false | truelead |
| NFC | true | true |
| OS | WearOS | WearOS |
Frequently asked
Which has longer battery life, OnePlus Watch 3 or Pixel Watch 3 (45mm)?+
OnePlus Watch 3 lasts 120h vs 36h.
Do OnePlus Watch 3 or Pixel Watch 3 (45mm) support ECG?+
Both support ECG.
Which has cellular, OnePlus Watch 3 or Pixel Watch 3 (45mm)?+
Pixel Watch 3 (45mm) offers a cellular variant; OnePlus Watch 3 is Wi-Fi only.
Spec-level deep dives
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