Where they actually differ
The most decisive specs, ranked by how much they matter — before the full spec table.
| Spec | OnePlus 15 | Xiaomi 15 |
|---|---|---|
| Battery capacity | 7500 mAh | 5400 mAh |
| RAM | 16 GB | 12 GB |
| Wired charging | 120 W | 90 W |
| Weight | 211 g | 192 g |
| AnTuTu | 2950000 | 2680000 |
| Screen size | 6.78 " | 6.36 " |
Between the OnePlus 15 and Xiaomi 15, the OnePlus 15 comes out ahead in battery capacity / ram, while the Xiaomi 15 wins on weight / pixel density. Overall, the OnePlus 15 scores 76.7 and the Xiaomi 15 scores 69.8 on our Mars Score.
Which should you buy?
The OnePlus 15 edges ahead on the Mars Score (76.7 vs 69.8), but the 6.9-point gap is small enough that the right pick comes down to which spec advantages matter to you.
Pick the OnePlus 15 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 capacity, ram, wired charging, among others. The single most decisive one: Battery capacity — 38.89% more. 7500 mAh vs 5400 mAh.
Pick the Xiaomi 15 if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. Its strongest claims are weight, pixel density. The single most decisive one: Weight — 19.00 g less. 192 vs 211.
Both ship with comparable main camera, refresh rate, 5g support, so those specs do not separate the two — focus on the differences below.
Bottom line: the OnePlus 15 is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Which should you buy: OnePlus 15 or Xiaomi 15?
OnePlus 15 leads the current Mars Score by 6.9 points.The more useful decision is the trade-off behind that result: compare screen size, ram, pixel density, battery capacity against the way you will actually use the product.
Choose OnePlus 15 if…
OnePlus 15 has the measurable edge on battery capacity mah, ram gb, wired charging w.
Choose Xiaomi 15 if…
Xiaomi 15 has the measurable edge on weight g, pixel density ppi.
This is a structured comparison of the published catalog values. It is not a claim of identical real-world performance across every workload; use the linked spec drill-downs and methodology page to inspect the inputs.
Why OnePlus 15 wins
- ▲Battery capacity — 38.89% more. 7500 mAh vs 5400 mAh.
- ▲RAM — 33.33% more. 16 GB vs 12 GB.
- ▲Wired charging — 33.33% more. 120 W vs 90 W.
- ▲AnTuTu — 10.07% more. 2950000 vs 2680000.
- ▲Screen size — 6.60% more. 6.78 " vs 6.36 ".
- ▲Water resistance: IP69 (vs IP68).
- ▲Promised OS updates: 5 (vs 4).
Why Xiaomi 15 wins
- ▲Weight — 19.00 g less. 192 vs 211.
- ▲Pixel density — 2.22% more. 460 ppi vs 450 ppi.
Spec comparison
Design
| Spec | OnePlus 15 | Xiaomi 15 |
|---|---|---|
| Weight | 211 g | 192 glead |
| Thickness | 8.3 mm | 8.1 mmlead |
| Water resistanceⓘ | IP69lead | IP68 |
| Form factor | bar | bar |
Display
| Spec | OnePlus 15 | Xiaomi 15 |
|---|---|---|
| Screen size | 6.78 "lead | 6.36 " |
| Pixel densityⓘ | 450 ppi | 460 ppilead |
| Refresh rateⓘ | 120 Hz | 120 Hz |
| Peak brightnessⓘ | 4500 nitslead | 3200 nits |
Performance
| Spec | OnePlus 15 | Xiaomi 15 |
|---|---|---|
| RAMⓘ | 16 GBlead | 12 GB |
| Storageⓘ | 512 GBlead | 256 GB |
| AnTuTuⓘ | 2950000lead | 2680000 |
| CPU total clockⓘ | 23.6 GHzlead | 22.8 GHz |
Cameras
| Spec | OnePlus 15 | Xiaomi 15 |
|---|---|---|
| Main cameraⓘ | 50 MP | 50 MP |
| Front camera | 32 MP | 32 MP |
| Optical image stabilizationⓘ | true | true |
Battery
| Spec | OnePlus 15 | Xiaomi 15 |
|---|---|---|
| Battery capacityⓘ | 7500 mAhlead | 5400 mAh |
| Wired chargingⓘ | 120 Wlead | 90 W |
| Wireless chargingⓘ | 50 W | 50 W |
Connectivity
| Spec | OnePlus 15 | Xiaomi 15 |
|---|---|---|
| 5G supportⓘ | true | true |
| Headphone jack | false | false |
| microSD slot | false | false |
Operating System
| Spec | OnePlus 15 | Xiaomi 15 |
|---|---|---|
| OS | Android | Android |
| Promised OS updates | 5 yearslead | 4 years |
Frequently asked
Which has better battery, OnePlus 15 or Xiaomi 15?+
OnePlus 15 has 38.9% more battery — 7500 mAh vs 5400 mAh.
Which is lighter, OnePlus 15 or Xiaomi 15?+
Xiaomi 15 is 19g lighter — 211g vs 192g.
Is OnePlus 15 waterproof?+
OnePlus 15 has an IP69 rating.
Does Xiaomi 15 support 5G?+
Yes, Xiaomi 15 supports 5G.
Which has more RAM, OnePlus 15 or Xiaomi 15?+
OnePlus 15 offers 16GB of RAM.
Which has a better camera, OnePlus 15 or Xiaomi 15?+
Xiaomi 15 has a 50 MP main camera vs 50 MP.