Between the Galaxy Watch 6 Classic and OnePlus Watch 3, the Galaxy Watch 6 Classic comes out ahead in weight and cellular, while the OnePlus Watch 3 wins on battery life and peak brightness. Overall, the Galaxy Watch 6 Classic scores 48.9 and the OnePlus Watch 3 scores 53.9 on our Mars Score.
Which should you buy?
The OnePlus Watch 3 edges ahead on the Mars Score (48.9 vs 53.9), but the 5.0-point gap is small enough that the right pick comes down to which spec advantages matter to you.
Pick the Galaxy Watch 6 Classic if you carry the device everywhere and weight or thickness has been the deciding factor before. The biggest gaps in its favor are weight, cellular.
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, peak brightness, display size.
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 Samsung - Galaxy Watch 6 Classic wins
- ▲Weight — 22.00 g less. 59 vs 81.
- ▲Has Cellular.
Why OnePlus Watch 3 wins
- ▲Battery life — 200.00% more. 120 h vs 40 h.
- ▲Peak brightness — 10.00% more. 2200 nits vs 2000 nits.
- ▲Display size — 2.04% more. 1.5 " vs 1.47 ".
Spec comparison
Design
| Spec | Samsung - Galaxy Watch 6 Classic | OnePlus Watch 3 |
|---|---|---|
| Case size | 47 mmlead | 46.5 mm |
| Weight | 59 glead | 81 g |
| Case material | stainless steel | stainless steel |
| Water resistanceⓘ | 5 ATM | 5 ATM |
Display
| Spec | Samsung - Galaxy Watch 6 Classic | OnePlus Watch 3 |
|---|---|---|
| Display size | 1.47 " | 1.5 "lead |
| Always-on display | true | true |
| Peak brightnessⓘ | 2000 nits | 2200 nitslead |
Health & Fitness
| Spec | Samsung - Galaxy Watch 6 Classic | OnePlus Watch 3 |
|---|---|---|
| ECG | true | true |
| SpO2 | true | true |
| Temperature sensor | true | true |
| Sleep tracking | true | true |
| Blood pressure | truelead | false |
Battery & Connectivity
| Spec | Samsung - Galaxy Watch 6 Classic | OnePlus Watch 3 |
|---|---|---|
| Battery life | 40 h | 120 hlead |
| GPS | true | true |
| Cellular | truelead | false |
| NFC | true | true |
| OS | WearOS | WearOS |
Frequently asked
Which has longer battery life, Galaxy Watch 6 Classic or OnePlus Watch 3?+
OnePlus Watch 3 lasts 120h vs 40h.
Do Galaxy Watch 6 Classic or OnePlus Watch 3 support ECG?+
Both support ECG.
Which has cellular, Galaxy Watch 6 Classic or OnePlus Watch 3?+
Galaxy Watch 6 Classic offers a cellular variant; OnePlus Watch 3 is Wi-Fi only.
Spec-level deep dives
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