Between the Watch Ultra 2 and OnePlus Watch 3, the Watch Ultra 2 comes out ahead in peak brightness and display size, while the OnePlus Watch 3 wins on battery life. Overall, the Watch Ultra 2 scores 60.5 and the OnePlus Watch 3 scores 53.9 on our Mars Score.
Which should you buy?
The Watch Ultra 2 edges ahead on the Mars Score (60.5 vs 53.9), but the 6.6-point gap is small enough that the right pick comes down to which spec advantages matter to you.
Pick the Watch Ultra 2 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, weight, among others.
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. Its strongest claims are battery life.
Both ship with comparable ecg, spo2, so those specs don't separate the two — focus on the differences below.
Bottom line: the Watch Ultra 2 is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Apple - Watch Ultra 2 wins
- ▲Peak brightness — 36.36% more. 3000 nits vs 2200 nits.
- ▲Display size — 28.00% more. 1.92 " vs 1.5 ".
- ▲Weight — 19.60 g less. 61.4 vs 81.
- ▲Water resistance — 5.00 ATM more. 10 vs 5.
- ▲Has Cellular.
Why OnePlus Watch 3 wins
- ▲Battery life — 233.33% more. 120 h vs 36 h.
Spec comparison
Design
| Spec | Apple - Watch Ultra 2 | OnePlus Watch 3 |
|---|---|---|
| Case size | 49 mmlead | 46.5 mm |
| Weight | 61.4 glead | 81 g |
| Case material | titanium | stainless steel |
| Water resistanceⓘ | 10 ATMlead | 5 ATM |
Display
| Spec | Apple - Watch Ultra 2 | OnePlus Watch 3 |
|---|---|---|
| Display size | 1.92 "lead | 1.5 " |
| Always-on display | true | true |
| Peak brightnessⓘ | 3000 nitslead | 2200 nits |
Health & Fitness
| Spec | Apple - Watch Ultra 2 | OnePlus Watch 3 |
|---|---|---|
| ECG | true | true |
| SpO2 | true | true |
| Temperature sensor | true | true |
| Sleep tracking | true | true |
| Blood pressure | false | false |
Battery & Connectivity
| Spec | Apple - Watch Ultra 2 | OnePlus Watch 3 |
|---|---|---|
| Battery life | 36 h | 120 hlead |
| GPS | true | true |
| Cellular | truelead | false |
| NFC | true | true |
| OS | watchOS | WearOSlead |
Frequently asked
Which has longer battery life, Watch Ultra 2 or OnePlus Watch 3?+
OnePlus Watch 3 lasts 120h vs 36h.
Do Watch Ultra 2 or OnePlus Watch 3 support ECG?+
Both support ECG.
Which has cellular, Watch Ultra 2 or OnePlus Watch 3?+
Watch Ultra 2 offers a cellular variant; OnePlus Watch 3 is Wi-Fi only.
Spec-level deep dives
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