Between the Phone (3a) and Xiaomi 15 Pro, the Phone (3a) comes out ahead in weight and screen size, while the Xiaomi 15 Pro wins on antutu and ram. Overall, the Phone (3a) scores 62.5 and the Xiaomi 15 Pro scores 74 on our Mars Score.
Which should you buy?
The Xiaomi 15 Pro is the clear pick on raw spec strength, leading by 11.5 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
Pick the Phone (3a) 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 weight, screen size.
Pick the Xiaomi 15 Pro 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, ram, wired charging, 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 Xiaomi 15 Pro 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 — 12.00 g less. 201 vs 213.
- ▲Screen size — 0.59% more. 6.77 " vs 6.73 ".
Why Xiaomi 15 Pro wins
- ▲AnTuTu — 230.49% more. 2710000 vs 820000.
- ▲RAM — 100.00% more. 16 GB vs 8 GB.
- ▲Wired charging — 80.00% more. 90 W vs 50 W.
- ▲Pixel density — 34.88% more. 522 ppi vs 387 ppi.
- ▲Battery capacity — 22.00% more. 6100 mAh vs 5000 mAh.
- ▲Water resistance: IP68 (vs IP64).
- ▲Promised OS updates: 4 (vs 3).
- ▲Wireless charging: 50 W vs 0 W.
Spec comparison
Design
| Spec | Nothing - Phone (3a) | Xiaomi 15 Pro |
|---|---|---|
| Weight | 201 glead | 213 g |
| Thickness | 8.4 mm | 8.4 mm |
| Water resistanceⓘ | IP64 | IP68lead |
| Form factor | bar | bar |
Display
| Spec | Nothing - Phone (3a) | Xiaomi 15 Pro |
|---|---|---|
| Screen sizeⓘ | 6.77 "lead | 6.73 " |
| Pixel densityⓘ | 387 ppi | 522 ppilead |
| Refresh rateⓘ | 120 Hz | 120 Hz |
| Peak brightnessⓘ | 3000 nits | 3200 nitslead |
Performance
Cameras
| Spec | Nothing - Phone (3a) | Xiaomi 15 Pro |
|---|---|---|
| Main cameraⓘ | 50 MP | 50 MP |
| Front camera | 32 MP | 32 MP |
| Optical image stabilizationⓘ | true | true |
Battery
| Spec | Nothing - Phone (3a) | Xiaomi 15 Pro |
|---|---|---|
| Battery capacity | 5000 mAh | 6100 mAhlead |
| Wired chargingⓘ | 50 W | 90 Wlead |
| Wireless chargingⓘ | 0 W | 50 Wlead |
Connectivity
| Spec | Nothing - Phone (3a) | Xiaomi 15 Pro |
|---|---|---|
| 5G supportⓘ | true | true |
| Headphone jack | false | false |
| microSD slot | false | false |
Operating System
| Spec | Nothing - Phone (3a) | Xiaomi 15 Pro |
|---|---|---|
| OS | Android | Android |
| Promised OS updates | 3 years | 4 yearslead |
Frequently asked
Which has better battery, Phone (3a) or Xiaomi 15 Pro?+
Xiaomi 15 Pro has 22.0% more battery — 5000 mAh vs 6100 mAh.
Which is lighter, Phone (3a) or Xiaomi 15 Pro?+
Phone (3a) is 12g lighter — 201g vs 213g.
Is Phone (3a) waterproof?+
Phone (3a) has an IP64 rating.
Does Xiaomi 15 Pro support 5G?+
Yes, Xiaomi 15 Pro supports 5G.
Which has more RAM, Phone (3a) or Xiaomi 15 Pro?+
Xiaomi 15 Pro offers 16GB of RAM.
Which has a better camera, Phone (3a) or Xiaomi 15 Pro?+
Xiaomi 15 Pro has a 50 MP main camera vs 50 MP.
Spec-level deep dives
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