Between the Phone (3a) and OnePlus 12, the Phone (3a) comes out ahead in weight, while the OnePlus 12 wins on antutu and wired charging. Overall, the Phone (3a) scores 62.5 and the OnePlus 12 scores 69.6 on our Mars Score.
Which should you buy?
The OnePlus 12 edges ahead on the Mars Score (62.5 vs 69.6), but the 7.1-point gap is small enough that the right pick comes down to which spec advantages matter to you.
Pick the Phone (3a) if you carry the device everywhere and weight or thickness has been the deciding factor before. The biggest gaps in its favor are weight.
Pick the OnePlus 12 if you push the hardware — gaming, on-device AI, heavy multitasking — and the extra compute headroom is worth the trade-offs. Its strongest claims are antutu, wired charging, ram, among others.
Both ship with comparable main camera, refresh rate, 5g support, so those specs don't separate the two — focus on the differences below.
Bottom line: the OnePlus 12 is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Nothing - Phone (3a) wins
- ▲Weight — 19.00 g less. 201 vs 220.
Why OnePlus 12 wins
- ▲AnTuTu — 151.22% more. 2060000 vs 820000.
- ▲Wired charging — 100.00% more. 100 W vs 50 W.
- ▲RAM — 50.00% more. 12 GB vs 8 GB.
- ▲Pixel density — 31.78% more. 510 ppi vs 387 ppi.
- ▲Battery capacity — 8.00% more. 5400 mAh vs 5000 mAh.
- ▲Screen size — 0.74% more. 6.82 " vs 6.77 ".
- ▲Water resistance: IP65 (vs IP64).
- ▲Promised OS updates: 4 (vs 3).
Spec comparison
Design
| Spec | Nothing - Phone (3a) | OnePlus 12 |
|---|---|---|
| Weight | 201 glead | 220 g |
| Thickness | 8.4 mmlead | 9.15 mm |
| Water resistanceⓘ | IP64 | IP65lead |
| Form factor | bar | bar |
Display
| Spec | Nothing - Phone (3a) | OnePlus 12 |
|---|---|---|
| Screen sizeⓘ | 6.77 " | 6.82 "lead |
| Pixel densityⓘ | 387 ppi | 510 ppilead |
| Refresh rateⓘ | 120 Hz | 120 Hz |
| Peak brightnessⓘ | 3000 nits | 4500 nitslead |
Performance
Cameras
| Spec | Nothing - Phone (3a) | OnePlus 12 |
|---|---|---|
| Main cameraⓘ | 50 MP | 50 MP |
| Front camera | 32 MP | 32 MP |
| Optical image stabilizationⓘ | true | true |
Battery
| Spec | Nothing - Phone (3a) | OnePlus 12 |
|---|---|---|
| Battery capacity | 5000 mAh | 5400 mAhlead |
| Wired chargingⓘ | 50 W | 100 Wlead |
| Wireless chargingⓘ | 0 W | 50 Wlead |
Connectivity
| Spec | Nothing - Phone (3a) | OnePlus 12 |
|---|---|---|
| 5G supportⓘ | true | true |
| Headphone jack | false | false |
| microSD slot | false | false |
Operating System
| Spec | Nothing - Phone (3a) | OnePlus 12 |
|---|---|---|
| OS | Android | Android |
| Promised OS updates | 3 years | 4 yearslead |
Frequently asked
Which has better battery, Phone (3a) or OnePlus 12?+
OnePlus 12 has 8.0% more battery — 5000 mAh vs 5400 mAh.
Which is lighter, Phone (3a) or OnePlus 12?+
Phone (3a) is 19g lighter — 201g vs 220g.
Is Phone (3a) waterproof?+
Phone (3a) has an IP64 rating.
Does OnePlus 12 support 5G?+
Yes, OnePlus 12 supports 5G.
Which has more RAM, Phone (3a) or OnePlus 12?+
OnePlus 12 offers 12GB of RAM.
Which has a better camera, Phone (3a) or OnePlus 12?+
OnePlus 12 has a 50 MP main camera vs 50 MP.
Spec-level deep dives
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